The Provo Tabernacle Fire Origin, Cause, and Circumstance

Transcription

1 The Provo Tabernacle Fire Origin, Cause, and Circumstance December 17, 2010 Incident: Report Date: March 31, 2011

2 Abstract The Origin, Cause and Circumstance of the Provo Tabernacle Fire At 0243 on December 17, 2010, a fire was reported at the Provo Tabernacle by an off-duty Provo Police Officer, working as a private security guard. The security guard identified two areas of fire. The first area of fire identified was located near the center of the elevated stage. The second area of fire was located in the ceiling where a 10 x 20 foot hole oriented from east to west had appeared. Fire was visible around the edge of the hole in the ceiling. The fire continued to burn until the entire roof collapsed and the debris in the structure burned until approximately 1500 hours on Saturday, December 18, An investigative Task Force from Provo City and the Utah State Fire Marshal s Office was established to determine origin, cause, and circumstances of this fire. The investigators worked to identify the heat source(s), the fuel (s), and the precipitating event that brought them all together, causing the fire. Using NFPA 921 as the reference standard, the following steps were completed. Identify the Problem The problem in this particular incident was that an uncontrolled fire consumed the roof structure and then the interior of the Provo Tabernacle. Define the Problem Specifically, a fire started high in the building and was undetected for a significant period of time. The fire was not reported at first detection. Investigators were aided by eyewitness statements about the location and size of the fire when reported. Based on eyewitness accounts, the area of fire origin was narrowed down to an area of the ceiling near two circuits of dimmable incandescent light fixtures. Collect Data The data collection began with the arrival of the first due fire units. Fire Marshal Lynn Schofield, the lead investigator on this incident arrived at Investigators were able to observe the initial fire behavior and then the fire progression. Photographs taken during the suppression activities provided details about the fire progression and the buildings response. Investigators interviewed witnesses including: the security guard, the lighting technicians, building coordinators, facilities maintenance personnel, BYU production staff, Gloria cast and crew members, and members of the public who had information about the circumstances surrounding this fire. Investigators took the information gathered from observations and witnesses and entered the structure on January 3, Over the next four weeks, the investigators located, diagrammed, i

3 photographed, and logged evidence of fire behavior and fire spread. The investigators, working from the least damaged to the most damaged, focused on the area around the elevated stage. Analyze Data and Hypothesis Development The data on hand led investigators to the development of two hypotheses. Hypothesis I A heat source, specifically an incandescent light fixture with an energized 300 watt lamp, placed too close to combustible materials is a legitimate proximate cause of the fire at the Provo Tabernacle reported December 17, Hypothesis II A fuel source when heated to its ignition temperature and in a glowing combustion will continue to combust until it runs out of fuel, does not have sufficient oxygen to sustain combustion, or is suppressed. Test the Hypothesis Both hypotheses were tested. Hypothesis I was supported as a proximate cause of the fire at the Provo Tabernacle, December 17, Hypothesis II was supported as an extension of the proximate causes identified in Hypothesis I. Select Final Hypothesis The Task Force has concluded that based on witness statements, observed fire behavior, and physical evidence, the most probable cause of the fire at the Provo Tabernacle was a heat source, specifically an incandescent light fixture, with an energized 300-watt lamp, placed too close to combustible materials. Specifically, a wooden speaker enclosure is identified as the most probable cause of the fire at the Provo Tabernacle reported December 17, Conclusions Area of Origin: The attic space in the area of the dimmable incandescent light system. Point of Origin: The most probable point of origin is the center speaker enclosure located between the two east dimmable incandescent light fixtures. These light fixtures were set aside to suspend the lighting truss. Cause: The cause of this fire is accidental. Proximate Cause: The proximate cause of the fire at the Tabernacle is a heat source placed too close to combustible materials. Heat Source: An incandescent light fixture with an energized 300-watt lamp. ii

4 Combustible Materials: A wooden speaker enclosure. Circumstances: The following circumstances contributed to the ignition, spread, and fire loss at the Provo Tabernacle, December 17, Inadequate fire detection and notification system. 2. The lack of an automatic sprinkler system. 3. Additional fuel load brought in as part of the set for the Gloria production. 4. Human Error. iii

5 Table of Contents ABSTRACT... i ABSTRACT... ii ABSTRACT... iii CONTENTS... iv LIST OF FIGURES...v LIST OF FIGURES... vi FOREWORD... vii FIRE DISCOVERY...1 FIRE DEPARTMENT RESPONSE...2 FIRE INVESTIGATION TASK FORCE INTERVIEWS BUILDING CONSTRUCTION AREA OF FIRE ORIGIN BUILDING EVACUATION AND DATA COLLECTION GENERAL OBSERVATIONS SITE EVACUATION... ORIGIN & CAUSE DETERMINATION AREA OF ORIGIN POINT OF ORIGIN CAUSE...50 HYPOTHESIS DEVELOPMENT HYPOTHESIS HYPOTHESIS 1 CONCLUSION HYPOTHESIS HYPOTHESIS 2 CONCLUSION...72 FIRE IGNITION AND SPREAD...72 CONCLUSIONS...80 APPENDIX A...86 APPENDIX B...92 APPENDIX C...94 iv

6 Figure 1: Location of Security Officer at Fire Discovery Figure 2: Fire Ground Orientation Figure 3: Initial Presentation Figure 4: Smoke Progression Figure 5: First Visible Flames Figure 6: Flame Progressions to Second Window Figure 7: Flame Progressions to Third Window Figure 8: Apparatus Set Up and Hose Stream Deployment Figure 9: Deteriorating Smoke Conditions Figure 10: Initial Roof Collapse Figure 11: Site Layout During Fire Operations Figure 12: Hazards Identified on the West Side of the Building Figure 13: Aerial View of Identified Hazards Figure 14: West Door Held Open with Duct Tape Figure 15: Site Layout at the Time of Fire Discovery Figure 16: Security Guard Williams Ground Floor Path of Travel at 0110 Figure 17: Security Guard Williams Balcony Level Path of Travel at 0110 Figure 18: Provo Tabernacle Fire Control Panel Figure 19: Autocall MD2 Fire Alarm Control Panel Figure 20: Autocall MD2 Fire Alarm Control Panel Detail Figure 21: Locations of Fire and Hole in the Ceiling Identified by Security Guard Williams Figure 22: Lighting Diagram Provided by Trax Lighting and AV Part I Figure 23: Lighting Diagram Provided by Trax Lighting and AV Part II Figure 24: Lighting Scheme Including In House Incandescent Lights and Lighting Truss Figure 25: Photograph of the Lighting Scheme Figure 26: Gloria Production Set Up Figure 27: Lighting Truss Suspensions in Tabernacle Attic Figure 28: Lighting Truss Suspensions in Attic with Diagram by Scott Morgan Figure 29: Aerial View of the Tabernacle Prior to the Fire Figure 30: Provo Tabernacle North Balcony Figure 31: Diagram of Provo Tabernacle Roof Structure Figure 32: Provo Tabernacle Roof Truss Figure 33: Fire Alarm Panel, HVAC Equipment and Electrical Breaker Panel Locations Figure 34: Grid Pattern for Tabernacle Site Excavation Figure 35: Large Debris Items Located in the Interior Figure 36: In-House Tabernacle Dimmer Control Box Figure 37: Physical Layout of the Tabernacle December 16, 2010 Figure 38: Physical Layout of the Tabernacle After Removal of Large Debris Figure 39: Location of Recovered Items Associated With the Lighting Truss Figure 40: Location of Recovered Items Associated with Incandescent Lights Figure 41: Provo Tabernacle Ceiling Joist Layout with Area of Fire Origin Figure 42: Initial Presentation of Smoke Conditions Figure 43: Visible Flames and Increased Smoke Turbulence Figure 44: Visible Flames Pushing Down From the Attic v

7 Figure 45: The Dimmable Incandescent Light Circuits Figure 46: Mock-Up Box Construction Figure 47: Light Fixture Lamp Figure 48: Light Fixture Profile Figure 49: Testing Set Up Figure 50: Mock-Up #1 Data Figure 51: Mock-Up #2 Data Figure 52: Mock-Up #1 Figure 53: Mock-Up #2 Figure 54: Mock-Up #3 Figure 55: Temperature Production in Mock-Up #3 Figure 56: Mock-Up #3 with Combustion Figure 57: Mock-Up #3 Self-Sustaining Glowing Combustion Figure 58: Mock-Up #3 Flaming Combustion Figure 59: Interior of Mock-Up #3 Figure 60: Char Depth in Mock-Up #3 Figure 61: Mock-Up #4 Set Up Figure 62: Mock-Up #4 Self-Sustaining Glowing Combustion Figure 63: Mock-Up #4 Self-Sustaining Glowing Construction Figure 64: Mock-Up #4 After 10 Hours of Glowing Combustion Figure 65: Mock-Up # 4 After 10 Hours of Glowing Combustion Figure 66: Point of Origin Figure 67: Point of Origin Interior View Figure 68: Available Attic Fuel Load and Heat Sources Figure 69: Initial Smoke Conditions Figure 70: Visible Flames Pushing Out of the Ceiling Figure 71: Location of First Roof Collapse Figure 72: Interior View of the Point of Origin Figure 73: The Point of Origin vi

8 Foreward On December 17, 2010, a fire originating in the attic of the historic Provo Tabernacle resulted in significant damage to the structure. Fire loss is estimated at 15 million dollars. Provo Fire & Rescue, the primary response agency and Authority Having Jurisdiction (AHJ), are bound by statute to determine the origin and cause of all fires within their jurisdiction. The Utah State Code reads Fire investigations by local officers Notification to division (1) The chief fire officer of any city, town, or county fire department, or of any fire district or special service district organized for fire protection purposes, or his authorized representative shall investigate the cause, origin, and circumstances of each fire occurring in his jurisdiction when property has been destroyed or damaged. In accordance with the law, Provo Fire and Rescue established physical custody of the Tabernacle located at 90 South University Avenue at 0244 on December 17, 2010, and maintained custody until 1900 hours January 21, 2011 for the purpose of determining the origin, cause, and circumstances of this fire. Provo Fire & Rescue was assisted in this investigation by the Utah State Fire Marshal s Office. The investigation was completed in accordance with the best practices of NFPA 921: Guide for Fire and Explosions Investigations. This report details the investigative process including: identification and definition of the problem, data collection and analysis, hypothesis development and testing, and the selection process for the final hypothesis. vii

9 At 0243 on Friday, December 17, 2010, Provo City Dispatch received a radio transmission from an off-duty Provo Police officer working as a security guard at the Provo Tabernacle. Incident would result in fire suppression operations lasting nearly 38 hours, followed by a comprehensive investigation that lasted for approximately 12 weeks. Fire Discovery At approximately 0239, Witness #1 (W-1), a security guard on duty at the Tabernacle was contacted by W-16, a security guard from NuSkin, who had noticed what he believed was smoke or steam coming from the top of the Tabernacle. W-1 entered the west door of the building, which had been taped in an unlocked position with duct tape, to check out the interior of the structure Figure 1 W-1 proceeded through the foyer area and took the north hallway to the northeast edge of the stage. The red star in Figure 1 indicates the position of W-1 after entering the building. Figure 1: Location of Security Officer at Fire Discovery N Not to Scale Once he reached this position, he stated that he saw fire on the stage near the piano. He described the fire as being about 10 feet in diameter with a flame height of between one and three feet. He then described a hole in the ceiling measuring approximately 10 feet by 20 feet in the center of the ceiling over the elevated platform. He stated there were flames visible around the edge of the hole, with the bottom layer of flame being just a few inches, and the flame at the top of the hole being approximately one foot. He stated there was very little smoke in the room and that he could see the ceiling very clearly. He then exited the building and called in the alarm via his 2-way radio. That alarm was received at

10 Fire Department Response A first alarm assignment was transmitted at 0243 hours. The alarm assignment included Truck 25 staffed with a Captain and Engineer, Rescue 25 staffed with two Firefighter/Paramedics, Engine 24 staffed by a Captain (C-25) and Engineer, Rescue 24 staffed with two Firefighter/Paramedics, Squad 21 (S-21) staffed with two Firefighter/Paramedics, and Battalion 22 staffed by one Battalion Chief. While en route, Captain 24 radioed that smoke was visible from 400 South in the area of the Tabernacle. Truck 25 arrived on scene at 0244 and Captain 25 took command of the incident and confirmed a working structure fire. At 0245, Captain 25 called for an additional alarm assignment and Station 23 was dispatched to the scene. Station 23 responded with Truck 23 staffed by a Captain and Engineer, and Rescue 23 staffed by two Firefighter/Paramedics. Included in the total on scene staffing during the initial two alarms were one Battalion Chief, three Captains, three Engineers, and eight Firefighter/Paramedics for a total initial staffing level of 15. Administrative notifications were sent out at Battalion 24 arrived at 0308, Battalion 23 arrived at 0322, Chief 22 arrived on scene at 0327, and Chief 21 arrived on scene at The deployment of resources is identified in Figure 2. Figure 2: Fire Ground Orientation Charlie (C) Bravo (B) Delta (D) T-23 Alpha (A) Not to Scale T-25 E-24 B-22 Truck 25 set up their ladder on the A-B corner. At approximately 0302, Captain 25 and Firefighters from Rescue 21 made entry to the structure through the west door. They found light smoke inside the building. When they reached the same area as W-1, they found flames 2

11 engulfing the piano and working up into the choir seating area on the B side. They were unable to see the ceiling. C-25 (W-9) also reported hearing debris falling in the vicinity of the Delta (D)-A area. The crew exited the building and reported their findings to Battalion 22, who had assumed command of the Tabernacle incident. The decision was made to use a defensive strategy and all personnel were ordered to operate from the exterior of the structure. Fire Progression and Fire Suppression Activities When Truck 25 arrived and set up their ladder, the fire presented as shown in Figure 3. Figure 3: Initial Presentation Note the black smoke in the B gable vent Note the black smoke from A gable vent. BYU Broadcast Trailer T-25 Ladder Generator used by TRAX Lighting and AV Photo courtesy of A. Williams As illustrated in the above photo, black smoke was clearly visible from the gable vents. Moving to the C-D side of the building also found black smoke coming from the gable vents. In addition, the soffit at the A-D roof line was beginning to show gray-black smoke. At that time, there was a very small amount of light gray smoke coming from the top window near the A-B corner. At that time, no flame is visible to the exterior. It is worth noting that when C-25 and R-21 made entry, there was only very light smoke showing in the large hall. The smoke was not pressurized and did not prevent the firefighters from walking in. By 0301, the fire had progressed to the point where smoke was beginning to come through the soffit on the A-C side of the building. Based on the presentation of the smoke, it can be reasonably concluded that the majority of the fire was high in the structure in the attic space. The fire identified by W-1, W-9 and W-10 indicate that even though there was a large fire burning inside of the assembly area, the bulk of 3

12 the combustion was taking place above the ceiling level. Figure 4 looks at the A side of the structure. Figure 4: Smoke Progression Note the light gray smoke coming from the soffit and top of the window Black smoke continues to come from the A gable vent Note the black smoke coming from the A-D soffit Photo courtesy of A. Williams At 0304, T-23 began flowing water from their elevated master stream into the D gable vent. Efforts were hampered by a large metal louver and an air-handling unit that was inside the attic space. At approximately 0305, the windows on the west side of the A wall failed and the first flame became visible. The fire progression is illustrated in Figures 5, 6, and 7 as visible through the A side windows. 4

13 Figure 5: First Visible Flames This photograph, taken at 03:05:06 shows the first flames visible from the exterior Photo courtesy of A. Williams 5

14 Figure 6: Flame Progressions to Second Window This photograph, taken at 03:05:18 shows the flame extending towards the D side of the structure Photo courtesy of A. Williams Figure 7: Flame Progressions to Third Window Note the increased smoke production and pressure, now that the fire has ventilation This photo, taken at 03:05:34 shows the continuation of fire spread towards the D side. Note that the flame is visible in the top ½ of the window. Photo courtesy of A. Williams 6

15 As illustrated in the previous photographs, once the first window failed the ventilation of the building and attic space enabled an increased rate of combustion. This series of photographs also demonstrates that the fire is high in the building, in the attic space. The photographs show fire at the ceiling level, but not in the lower half of any of the windows. At 0310, R-24 made entry through the doors on the D side. They advanced through the foyer and reported heavy smoke, but no flames visible on the ground floor. Due to the deteriorating conditions and the decision to use a defensive strategy, R- 24 was pulled out of the building and all interior operations ceased. It was at this point, the full defensive strategy was put into place. The fire attack utilized master streams on all three aerial ladders, a ground monitor, and a 2 ½ inch hand line. A 1 ¾ inch hand line would be placed into service later in the day. The fire continued to grow with flames visible throughout the A-B side. A change in smoke conditions was also noted on the C side as the smoke became darker and more turbulent. At 0328, the first visible fire appeared on the roof. At 0358, flames began to come through the top window on the B-A corner. By 0406, heavy black smoke was pushing from the C-D side of the building. At this time, most of the windows on the C and D side were intact. Figure 8 illustrates the position of the defensive fire attack lines. An orange diamond indicates where the first fire broke through the roof at Figure 8: Apparatus Set Up and Hose Stream Deployment Area fire first appeared on the roof at 0328 T-23 2 ½ inch hand line Not to Scale T-25 E-24 Ground monitor supplied by 5 inch line 7

16 Once the fire penetrated the roof, the consistency of the smoke went from a black to a gray, darkgray. The quantity of smoke being produced also increased. The only visible fire in the interior of the building was in the top level of the building, near the ceiling. However, the smoke level continued to drop. Figure 9 shows deteriorating smoke conditions. Figure 9: Deteriorating Smoke Conditions Photo courtesy of Tree Gore At approximately 0430, a section of the roof on the B side collapsed. The collapse resulted in a significant change in the fire dynamics. It should be noted here that when this portion of the roof collapsed, it did not pull down the B gable end because the fire had already destroyed the truss structure. This section of roof collapsed within two hours of the discovery of the fire. Figure 10 shows the condition of the building following the collapse of the western section of the roof. 8

17 Figure 10: Initial Roof Collapse Photo courtesy of Tree Gore As this section of the roof collapsed, it exposed the fire at the ground level on the B side. As shown in the above photo, once this section collapsed there is no visible fire on the D side of the structure. However, the fire continues to actively burn in the roof structure. Fire suppression efforts continued throughout the morning. At approximately 0600, the remaining roof structure collapsed into the interior of the building. This portion of the roof collapsed within four hours of the discovery of the fire. When the remaining roof structure collapsed, the A-C-D gable ends of the masonry structure were pulled into the interior of the building. Once the roof collapsed, the fire continued to consume the interior of the structure, specifically the balcony areas. Fire suppression activities continued in the form of extinguishing hot spots within the shell of the structure, until approximately 1530 hours on Saturday, December 18, The fire suppression operations terminated at Fire Investigation Fire Marshal (FM) Lynn Schofield responded to the scene arriving at 0308 and after checking in with the IC Battalion Chief (BC) Roger Gourley, proceeded to do a 360-degree walk around of the building. Figure 11 shows the site layout at the time of his arrival. 9

18 Figure 11: Site Layout During Fire Operations Generator for Production Trailer BYU Production Trailer Diamond Tent for Production Crew Trax AV Trailer Trax External Light Towers T-23 Generator for Trax AV Not to Scale 3246 T-25 E-24 B-24 B-22 During Fire Marshal Schofield s walk around the exterior of the building, black smoke was still visible at all four gable vents. The smoke was pushing, but not turbulent. The upper level of windows also had gray smoke that was pushing, but not turbulent. The smoke that was presenting on the C side of the building was lighter in color and in only one window; the upper C-B window had failed at this point. No flames were visible on either the C or D sides. All of the smoke present was in the upper portions of the upper windows and soffits. All of the flame visible on the A side of the building, was located high on the ceiling. The bulk of the fire appeared to be high in the building above the level of the ceiling. Following the initial walk- around, the FM was briefed by the IC regarding the concert that was scheduled for the evening of December 17 and that a dress rehearsal was held on the preceding evening. The production was supposed to be recorded, so the building had a large amount of television production equipment inside. The two generators and a semi-sized production trailer were there to support the recording of the concert. Dan Stubbs, Provo City Chief Building Official was notified and responded to the incident. The Utah State Fire Marshal s Office was advised of the fire and requested to assist in the investigation. A Task Force briefing was scheduled for Saturday, December 18, 2010 at

19 The determination was made that it was not necessary to assemble the Task Force until the bulk of the fire suppression operations were completed. The FM was informed there may have been an alarm at the Tabernacle at approximately The IC identified W-1 Williams, the security guard that was on duty at the Tabernacle. W-1 Williams was asked to fill out a written witness statement. He went to the Mobile Emergency Operations Center (MEOC) van to complete the statement. At approximately 0430, a status briefing was held in the MEOC van with the Fire Department Command staff. Following that briefing, contact was made with representatives of the property owner and a status meeting was scheduled at Fire Station 21 conference room for At approximately 0600, FM met with W-1 Williams and received his written statement. The FM also gathered contact information and advised him that the Task Force would most likely want to speak with him. At 0930, Chief Blair Camp, Deputy Chief (DC) Gary Jolley, and Fire Marshal (FM) Lynn Schofield returned to Fire Station 21 to prepare for the status meeting. At that time, the statement from W-1 Williams was reviewed by Chief Camp and FM Schofield. At 1000, the first status meeting was held at Fire Station 21. The meeting was moved into the Community Development conference room due to the number of participants. The purpose of the meeting was to give an overview of the events to this point, coordinate media relations, and begin the process of securing the site. It was determined that the property owner would provide fencing to enclose the site. The fence would run down the east side of the NuSkin parking terrace to a point about one-halfway down the park to the north of the Tabernacle, turn east to the inside of the curb on University Avenue, and proceed south to the south side of 100 North. The fence would then turn west and run along the south side of 100 West to the East side of the upper post office parking lot. The fence line would then move north to the southern solid yellow stripe and continue to the west back to the beginning point. Gate access would be provided at University Avenue and 100 West. On December 20, 2010, the fence line was extended to Center Street in order to include the entire park. The fence was set up in the center of the road to accommodate post office traffic. The fence was to be put into place by Friday evening. The fence along 100 South consisted of fence panels that could be easily moved. Arrangements were also made to bring in two port-a-potties. The post office had been providing restrooms until they closed at 1700 hours. Another issue discussed, was handling the intense media interest. Helen Anderson, Provo City Public Relations assisted Provo Fire & Rescue with media coordination. Also discussed were the projected needs in the transition from fire suppression operations, the investigation of the fire, and future plans for the building. The group was informed that the fire suppression operations would likely continue through the next morning. Upon completion of the fire suppression operations, the building would have to be evaluated to determine if it was safe for the investigation into the origin, cause, and circumstance of the fire. A site visit with structural engineers was scheduled for Saturday, 18 December 2011 at Following the briefing, the engineers would be escorted to the site to determine the structural stability of the building. Chief Building Official Dan Stubbs was requested to attend that briefing and provide technical expertise. 11

20 It was noted, that the Task Force of fire investigators including investigators from the Utah State Fire Marshals Office and Provo Fire & Rescue, would also be assembling on Saturday to begin the origin and cause investigation. The property owner was invited to have an representative present. A question was asked about a reported alarm at the building at 0110 that morning. The group was advised that we had been made aware of that rumor, but had not yet had time to follow up. A copy of the cast and crew roster and contact information was requested from Tyler Weston, who was the producer for KBYU Broadcasting. On Saturday December 18, 2010, representatives of Provo Fire & Rescue and the Provo City Building Department met with representatives of the property owner, insurance agents, insurance adjusters and structural engineers to determine the stability of the remaining masonry shell. A briefing was presented that covered the current status of fire suppression operations, a safety briefing regarding the site visit, and the establishment of priorities for the site visit. The priorities we established were: 1. Safety a briefing was held and additional safety considerations were given at the site. Each participant was required to have a hard hat, safety glasses, and sturdy shoes. They were also briefed about slip and fall hazards from accumulated ice and snag and falling debris hazards from unstable gutters, soffit, and bricks still in place. 2. Hazard Mitigation the purpose of the initial site visit was to determine, to the best of their ability, the structural stability of the remaining shell. This determination, made with limited information, was specific to fire operations and the pending fire origin and cause determination. 3. Property Conservation the site visit also provided the adjustors, architects, and engineers with their first look at the remaining shell. It is our hope the information received from the site would allow them to begin to develop a strategy for the long-term status of the building. Once the priorities were established, the group relocated to the site. The group checked in with IC, Battalion Chief Tom Augustus and then split into several groups to tour the site. Chief Camp, DC Jolley, BC Augustus, Deputy Fire Marshal (DFM) Adams, FM Schofield escorted the groups around the exterior of the building and also into the NW turret. Because photographs were taken, the participants were informed both in the briefing and onsite that any photographs taken from inside of the fence line would be considered proprietary and should not be released or posted without the consent of the property owner. The site visit lasted for approximately one and one half hours. Upon completion of the site visit, the group returned to Fire Station 21 to discuss their findings and a proposed course of action. The consensus finding of the engineers was that there were two areas of concern. They were: 12

21 1. The west (Bravo) wall. When the roof collapsed, a section of the roof structure remained intact, anchored to the west gable. In addition, the large metal lightning arrestor had become dislodged and was only supported by a wire cable. 2. The south (Alpha) entrance. There was a large amount of debris located at the balcony level that presented a clear fall hazard. Figure 12 shows the west gable end and Figure 13 illustrates the concern at the south entrance. Figure 12: Hazards Identified on the West Side of the Building West gable end roof overhang is a stability concern. Photo by T. Mills Lightning Arrestor SW Turret The structural engineers recommended that no work, including origin and cause investigation takes place in the western half of the building. The engineers recommended that the lightning arrestor hanging on the SW turret be secured, the remaining roof structure on the west gable end removed, and the west gable end to be either secured in structural scaffolding or strategically demolished. Prior to any work completed on the interior of the structure, these items had to be completed. Figure 13 shows the balcony area above the south A entrance. The structural engineers recommended the loose bricks on the top of all walls, as well as burned out soffit and gutters are removed to reduce the falling debris hazard. They also recommended clearing off the south balcony area inside the entrance and the removal of some burned out balcony and stairs. Both the west end and south entrance were taped off as hazard areas, and the contractor, Jacobsen Construction, was instructed to render the building safe for investigators. Jacobsen crews began the stabilization work on Monday, December 20, Everyone entering the site was required to check in with security when they arrived and check out when they left. 13

22 Figure 13: Aerial View of Identified Hazards Falling bricks, structural members that are burned through and collapsed debris are areas of concern. Lightning Arrestor and remaining roof structure are the west end concerns Photo courtesy of UHP After completing the discussion pertaining to the stabilization of the structure, a series of briefings were established. The briefings would be held on Monday mornings at 0800 at Fire Station 21. The briefings were intended to keep participants informed of status changes and progress being made. The meeting adjourned at approximately After a short break the initial briefing for the members of the Provo Tabernacle Fire Task Force was conducted. Those present for the initial briefing were: Chief Blair Camp Provo Fire & Rescue Deputy Chief Gary Jolley Provo Fire & Rescue Fire Marshal Lynn Schofield Provo Fire & Rescue Chief Deputy State Fire Marshal Brent Halladay State Fire Marshal s Office Deputy State Fire Marshal Kim Passey State Fire Marshal s Office Deputy State Fire Marshal Mike Young State Fire Marshal s Office Deputy State Fire Marshal Troy Mills State Fire Marshal s Office 14

23 Deputy State Fire Marshal Brian Thatcher State Fire Marshal s Office Deputy State Fire Marshal Matt Sacco State Fire Marshal s Office David Petersen Brigham Young University representing the property owner Excused from the briefing: Deputy Fire Marshal Brad Adams Provo Fire & Rescue The purpose of forming the Task Force was to determine the origin, cause, and circumstances involved in this loss. The Tabernacle fire represents an extremely high profile event with intense scrutiny. The Task Force was limited to individuals with a statutory responsibility to determine the origin and cause of this fire. The property owner, The Church of Jesus Christ of Latter-Day Saints was invited to provide a representative to coordinate all activities onsite. The priorities for the task force are as follows: 1. Maintain a safe working environment. 2. Determine, to the best of our ability, the location of the origin of the fire. 3. Determine, to the best of our ability, the cause of the fire. 4. Determine, to the best of our ability, the circumstances that precipitated the causative event, contributed to the fire spread, and increased fire loss. Following a short briefing, the task force relocated to the site to get an overview of the structure and damage present. This enabled the Task Force to develop a work plan for the excavation and processing of the structure. Task Force Interviews W-1 Austin Williams Mr. Williams was interviewed by the Task Force at approximately 1400 at Fire Station 21.Mr. Williams stated the company that he worked for, APS, had been contracted to watch the production equipment brought in for the broadcast and taping of the Gloria concert. It should be noted here, that Mr. Williams is a Provo City police officer who was off duty at the time of this detail. He indicated that his primary responsibility was to watch the two generators and the production trailer parked in the parking lot on the B side of the structure. He was also to ensure that no unauthorized people entered the building. Mr. Williams indicated that he arrived at approximately 2130 before the dress rehearsal was completed, so he sat in the audience and watched. He produced a photo, taken with his cell phone, of the stage area of the Tabernacle. Mr. Williams stated that when the dress rehearsal was completed, he made contact with W-6 Weston who showed him the building and ensured that all the doors were closed and locked with the exception of the west door. The west door would be the single point of access to the building. It was maintained in an unlocked state by placing duct tape around the panic hardware. The purpose of keeping the west door unlocked was to allow Williams to access the restrooms, check the production equipment, and reset the heating in the building. The heat needed to be reset every three hours to maintain the temperature for the plants and instruments left in the tabernacle overnight. The west door and duct tape over the panic bar are illustrated in Figure

24 Figure 14: West Door Held Open with Duct Tape Duct tape on the panic hardware to allow security guard access Photo by: L. Schofield Sign placed in doorway after the firewas discovered Mr. Williams stated that Mr. Weston asked him to reset the heat every three hours. After completing the walkthrough of the building, Mr. Williams positioned the APS van and his patrol car as illustrated in Figure 15. Figure 15 depicts the position of all vehicles at the time the fire was discovered at

25 Figure 15: Site Layout at the Time of Fire Discovery Generator for Production Trailer 3246 Patrol Car Trax AV Trailer BYU Production Trailer Generator for Trax AV West Door Not to Scale APS Van Between 2300 and 2315, the final members of the production crew left the Tabernacle. All of the cords attached to the production trailer, the production trailer generator, and the lighting generator were disconnected and placed inside of the west door and the northwest turret. At 0030, Mr. Williams drove around the perimeter of the Tabernacle block to get a view of the entire building. He noted nothing unusual at that time. At approximately 0110, Mr. Williams exited his patrol car to go into the Tabernacle and reset the heat. As he approached the west door, he heard an audible alarm sounding inside of the building. He contacted Provo City Dispatch via radio and asked if they were receiving an alarm from the Tabernacle. They stated they were not. He entered the building with the intention of clearing it of intruders. He did not turn on any lights, although the restroom lights were equipped with motion sensors that turned on when he entered. Mr. Williams stated that he entered the building through the west door and then continued down the south aisle. He then went up the stairs of the southeast turret and checked the balcony. He came down the stairs in the northeast turret and went down the north aisle. During the time he was clearing the building, Provo City Dispatch was attempting to contact a responsible party for the Tabernacle. Dispatch was finally able to contact W-6 Weston. Mr. Weston stated he would contact the building coordinator (W-7 Rasmussen) and get back to dispatch. During his walkthrough of the building, Williams noted a laptop computer that was on, on the stage, and in the balcony area he noted popping and crackling, which he attributed to the movement of the floor. He did not see or smell any smoke or fire. Figure 16 and Figure 17 shows his path and the area where he found the laptop and heard the noises. 17

26 Figure 16: Security Guard Williams Ground Floor Path of Travel at 0110 DN Laptop Computer Fire Alarm Panel and Horn Not to Scale UP Figure 17: Security Guard Williams Balcony Level Path of Travel at 0110 Area where W-01 heard crackling and popping. Not to Scale 18

27 After clearing the building for intruders, Mr. Williams went to west lobby and located the alarm panel. He reported that there was a yellow light indicating the attic zone. Mr. Williams did not know how to access the attic. At approximately 0130, dispatch notified Williams that Weston had called back and indicated that he made contact with the building coordinator. Dispatch advised Williams that Weston was told that it was a false alarm and he could go ahead and reset it. Williams attempted to reset the alarm; however, it would go back into alarm in 15 to 20 seconds. Mr. Williams was able to find an instruction manual and get the audible horn to silence. A copy of the dispatch transcript is included in Appendix A. In subsequent interviews, Mr. Williams indicated that he used the button above the reset button on the panel to get the alarm silenced. Figure 18 is the alarm panel from the Tabernacle while Figure 19 is the same make and model alarm panel that was installed by the same company around The panel in Figure 19 is located in the LDS Chapel located at 1402 South 580 West in Provo. Figure 18: Provo Tabernacle Fire Control Panel Photo by T. Mills 19

28 Figure 19: Autocall MD2 Fire Alarm Control Panel Photo by L. Schofield Figure 20 shows the fire alarm panel at 1402 South 580 West with the door open so that buttons and lights are visible. This illustrates the steps that Williams took to reset the alarm. Williams stated that he attempted to reset the alarm, but it kept going off in 10 to fifteen seconds. After reviewing the manual, he stated that he pressed the button above the reset and the alarm stayed silent. As is shown in Figure 20, the button above the reset button is labeled ACKN for acknowledge. The acknowledge button would have silenced the alarm; however, it did not reset it. The alarm would remain silent until it was reset or until another zone went into alarm. The second item of note is that in his written statement, Williams describes a flashing yellow light. The yellow light is a trouble indicator. 20

29 Figure 20: Autocall MD2 Fire Alarm Control Panel Detail Acknowledge Button Used to silence the alarm Alarm indicator light Reset Button Trouble indicator light (yellow) Photo by L. Schofield Mr. Williams then waited to see if the alarm would go off for a few moments and then returned to his patrol car sometime after At about 0240, Mr. Williams again exited his patrol car to check the heat and see if the alarm had gone off again. He was summoned over near the NuSkin parking terrace by W-16 who asked whether that was smoke or steam coming from the roof of the Tabernacle. Mr. Williams reentered the tabernacle and found what he described as a small fire, approximately 10 feet in diameter, on and around the Fazioli grand piano on the front stage. He also stated that he saw a large hole in the ceiling with fire around both the top and bottom edge. He stated that the flames on the stage were about three to four feet high. He did not see the lighting truss on the stage. Mr. Williams stated that he called dispatch and reported the fire. He then returned to the outside and moved the APS security van to the post office parking lot located across the street. He then moved his patrol car to the driveway entrance to be out of the way for firefighting operations. Figure 21 illustrates the path Mr. Williams took on his re-entry, the location of the fire on the stage, and the hole in the ceiling. 21

30 Figure 21: Locations of Fire and Hole in the Ceiling Identified by Security Guard Williams Position of W-01 Williams Observed fire on the stage Observed hole in the ceiling Not to Scale When asked why he did not call the fire department at the 0110 alarm, Williams stated that he believed the alarm to be an intruder or burglar alarm. He reiterated that he did not see or smell smoke or any other indication of a fire. When asked how much smoke was in the building when he reentered, Williams said that there was light smoke in the building, but he could see the ceiling clearly. He was given a main level floor plan and a balcony level plan. He marked where he heard the crackling and popping sound, the area of the fire on the stage, the area of fire in the ceiling, and the location of the lighting truss that was suspended above the stage. He diagramed them as requested and signed the diagram. The information contained in that diagram is illustrated in Figures 16, 17 and 20. W-2 Jeremy Ostler and W-3 Jeff Ostler The Ostlers were scheduled to be interviewed at 1200 on Saturday, December 18. They made contact with FM Schofield by phone and indicated that they had been summoned to meet with the investigators contracted by their insurance carrier prior to meeting with us. They were also delayed by poor weather-related road conditions. They arrived at approximately 1500 and were interviewed at Provo Fire Station

31 The interview began by asking Jeremy Ostler to identify several items of interest on a floor plan of the Tabernacle including the lighting truss, location of the power supply, and any control cables. Jeremy Ostler provided a lighting diagram for the production lights. This diagram is shown in Figure 22 and Figure 23. Figure 22: Lighting Diagram Provided by Trax Lighting and AV Part I 23

32 Figure 23: Lighting Diagram Provided by Trax Lighting and AV Part II 24

33 Trax Lighting and AV was contracted by BYU Broadcasting to provide lighting and audio services for the Gloria production. According to Jeremy Ostler, they began to load in their equipment on Wednesday afternoon and had the lighting truss strung by mid-afternoon on Thursday. Jeremy stated that W-7 Bob Rasmussen showed them around the attic and provided access. In subsequent interviews, Jeremy Ostler stated the attic was open and he did not require assistance to get into the attic. Jeremy Ostler stated that he removed two recessed lighting cans from the ceiling and set them aside. When asked if he removed the lamps, he stated that the cans were not connected to any power. Later in the interview, he indicated that the lights were tethered with a flex conduit and connected with wire nuts. He stated that the only house power that was used in the attic was to power the two chain motors that are used to hoist the lighting truss. Jeremy stated that he entered the attic for the final time at 2000 hours when he disconnected the pickles or controls for the chain motors. He also indicated that the lighting truss would have been approximately eight to ten feet from the ceiling. Figure 24 shows the location of the recessed lights and the light truss suspended from the attic space. Figure 24: Lighting Scheme Including In House Incandescent Lights and Lighting Truss 25

34 Lighting truss Recessed lights set aside to suspend lighting truss In-house dimmable circuits Not to Scale When asked where the power to the production lights came from, he stated that the power feeding the light truss was provided by the small generator located at the southwest corner of the building. The power cords to the lighting truss came into the building through the west door and then up in front of the north balcony, while the chain motors were supplied by a 10 gauge yellow extension cord plugged into a house outlet in the attic. Figure 25 shows the lighting truss and the power supplies for both the chain motors and the lighting truss. Figure 25: Photograph of the Lighting Scheme 26

35 Speaker Enclosure Incandescent lights removed to suspend the lighting truss Lighting truss Power supply to the lighting truss Power supply from attic to the chain motors Photo courtesy of Tyler Weston He stated that the power to all the production lighting was cut off prior to 2300 hours when he left the building and that the cables were coiled up inside of the west door. He stated that he was the last one out of the building that evening, except for the security guard. When Mr. Ostler was asked if he had removed the lamps from the incandescent lights that he moved to suspend the truss, he stated there were not any bulbs in the fixtures, although he did not say how he verified that. He also stated the fixtures were not connected to power. Later in the interview on December 18, he stated the fixtures were tethered with a flexible metal conduit and connected by exposed wire nuts. In a subsequent interview, he stated that he knew there were no lamps in the fixtures because they were light as a feather. Jeremy Ostler confirmed in subsequent interviews that he found the recessed can lights to be tethered with a flexible metal conduit. He also confirmed that he entered the attic between 2000 and 2030 hours and found nothing unusual. He stated that the dimmable incandescent lamps were controlled by a dimmer box. He indicated that he used his own box rather than the dimmer control owned by the church. The interview on December 18 concluded with arrangements being made to return the Trax Lighting and AV Trailer to the owners. It was determined that would happen on a later date. Mr. Jeff Ostler inquired about an alarm at the Tabernacle prior to the fire. FM Schofield informed him that we had heard that report, but were not able to comment on it because we had not verified it. W-4 David Knecht, W-5 Pete Crane 27

36 Mr. David Knecht was interviewed on December 21, 2010 at Fire Station 21. The Task Force was specifically interested in the condition of the lights in the dimmable incandescent light circuit. Mr. Crane stated that he had been in the Tabernacle on Thursday, December 16, 2010 between 1000 and 1100 and found the lighting truss suspended from the ceiling. He stated that he did not go into the attic space, and wondered if the lighting contractor had disarmed the light. When asked what he meant by disarmed, Crane stated that meant to unscrew or remove the lamp from the fixture. When Mr. Crane and Mr. Knecht were told that the contractor stated that there were no lamps in the fixtures, they stated that there were, in fact, lamps in the fixture as of the previous week. They further stated that if the dimmable lights were not disabled they would cause a fire. When asked about the electrical wiring for the dimmable circuit, Mr. Knecht stated that the wiring was all contained in conduit. When asked if there were any fixtures in the circuit that were connected by exposed wire nuts, they stated that they were not aware of any. Mr. Knecht then stated that the entire conduit was located in the interstitial space and the wiring was contained in junction boxes. Mr. Crane stated that on December 8, 2010, he was in the attic working on an incandescent light that had been removed for the live nativity. He stated that all of the fixtures had lamps in them. They stated that if a light burned out the building manager would call them to replace it, because it was a point of emphasis for visiting authorities. Several times during the initial interview, both Mr. Knecht and Mr. Crane were emphatic that every fixture in the ceiling had a lamp in place. During a subsequent interview, Mr. Crane indicated that the northeast incandescent light was burned out and had not been replaced at the time of the fire. Mr. Knecht stated that the roof was 25 feet above the plywood deck at the highest point of the attic and that a person could walk throughout the attic. They stated there were air handling units in both ends of the building and ducting throughout the attic space. The ducts had wooden bridges over them. They indicated that the dimmer system was manufactured by Lehigh and installed by Greg Greenhalgh of G & G Electric. When asked about the status of the fire alarm system, Mr. Knecht stated that the alarm system was installed in They indicated that the NW turret was the most frequent source of false alarms followed by alarms began in the attic space. Mr. Knecht indicated that the system was old and it was increasingly difficult, if not impossible, to find parts. He further stated that the alarm system was tested on December 2, 2010 and that it failed. He indicated that the testing had been performed by BJ Mills of BEST Electric. When asked what size the bulbs would have been in the incandescent lights, neither Crane nor Knecht could recall exactly, but stated they were between 150 and 300 watts. Matt Ward, who oversaw the maintenance of the Tabernacle, was contacted and requested to acquire three of the bulbs that would have been used in the incandescent lights. W-7 Robert Rasmussen Robert Rasmussen was interviewed on December 27, 2010 at Provo Fire Station 21. Mr. Rasmussen was the building coordinator for the Provo Tabernacle. He has held that position for approximately five years. He was serving as a church service missionary and was responsible for coordinating other missionaries, scheduling the facility, and coordinating various activities including performances, organ practices, and other events. Mr. Rasmussen stated that he was over at the Tabernacle at 2030 on Thursday, December 16, He states that he was there until about 2130 hours. He states that he did not see or smell anything unusual during his time there. Mr. Rasmussen received a phone call from Tyler Weston who informed him there was an alarm sounding at the Tabernacle. Mr. Rasmussen stated that he received the first call at approximately 28

37 0230 informing him of the alarm, and a second call about 15 minutes later informing him of a small fire in the attic. It should be noted here that Mr. Rasmussen s recollection of the time line is not supported by the time-stamped records in dispatch. He states that he received several phone calls from Weston Thursday evening indicating that breakers were tripping. Mr. Rasmussen did not recall which breakers were tripping. Mr. Rasmussen stated that approximately one week prior to this incident, there had been a false alarm. At that time, the panel indicated that the alarm was in the attic. He accessed the attic, but didn t find anything unusual. He returned to the panel and reset the alarm. He stated that the alarm went off again and he again accessed the attic and reset the alarm. We asked how often they had false alarms in the attic. He stated that they occurred about twice a month. Mr. Rasmussen stated that it did not take any special knowledge or instruction to reset the alarm. Mr. Rasmussen stated that the lighting contractor was not given access to the attic to suspend the lighting truss. He stated that Jeremy Ostler told him that he used his own keys until one of the keys opened the door. Mr. Rasmussen stated that no one from the missionary group opened the attic door for Jeremy Ostler. Mr. Rasmussen stated that if you took the light out, but didn t take the light (lamp) out of the container that it is in... we told him (Mr. Ostler) that you have to take the lights out. He did not know whether they removed the lamps from the two fixtures that were removed to suspend the truss. Mr. Rasmussen stated that he was positive there were bulbs in the fixtures on Tuesday, December 14. If the bulbs were out, he would call Pete Crane or David Knecht to replace them. Mr. Rasmussen stated that when Mr. Weston called, he gave him instructions to get the security guard to the alarm panel. He states that he did not have a conversation with Mr. Weston to instruct him on the steps to reset the alarm. Mr. Rasmussen stated that he instructed Mr. Weston to have the security officer access the attic and then call him back. Mr. Rasmussen stated that he did not instruct Mr. Weston to reset the alarm panel. He stated that he may have told Mr. Weston the alarm system may be finicky. Mr. Rasmussen stated that at no time did he give the lighting contractors a key to access the attic. In a subsequent interview, Mr. Rasmussen states that he did instruct Mr. Weston to have the security officer reset the alarm at approximately W-6 Tyler Weston Tyler Weston was interviewed on December 27, 2010 at Provo Fire Station 21. Mr. Weston was the producer for BYU Broadcasting who were scheduled to record the Gloria Production. Mr. Weston stated that he became acquainted with Trax Lighting and AV through the composer of the Gloria production, Lex De Azevado. He stated that the original plan did not include a suspended lighting truss, but the contractor added it because they were not able to adequately light the set. He stated that he never went up into the attic nor did he find anything unusual about the lighting setup. He stated that the lighting contractor was in the building during the afternoon focusing the lights for the production. He was unable to recall whether the incandescent lights were on for the entire time. He stated that he received a phone call from Provo City Dispatch informing him of the alarm at the Tabernacle. He stated that he called Bob Rasmussen who told him that the alarm had been malfunctioning, and to go ahead and reset the alarm. He then called back Provo City Dispatch and instructed Mr. Williams to reset the alarm. He stated the security company was to watch over the cables and trucks. When further questioned, Weston indicated the contract surrounded the equipment and not necessarily the building. He stated that he asked the security guard to reset the heat throughout the night. When asked if he thought that it was unusual to reset an alarm without checking it out, he stated that at the time 29

38 it did not seem to be unusual. He also stated that he discussed the alarm system with members of the facilities maintenance group at the fire scene the night of the fire. He was then asked if he walked the security guard around the building, specifically, if he showed him how to access the attic, he stated that he had not. When asked if he was aware of any of the cast or crew who had reportedly smelled a hot glue gun type smell, he indicated that he had heard something like that from one of his camera operators, Brian Bunton. W-8 Brian Bunton Mr. Bunton was interviewed on December 28, 2010 at Fire Station 21 by Lynn Schofield and David Petersen. He was a camera operator who was present during the dress rehearsal on December 16, He stated that he was operating Camera 2 in the balcony area of the Tabernacle during the dress rehearsal with Scott Morgan who was operating Camera 1. Their locations are shown in Figure 26. Figure 26: Gloria Production Set Up Light Tree Light truss Jib Unnumbered Cameras Camera 2 Camera 1 Camera 3 Projector and Screen so musicians can see the conductor. Light Tree Not to Scale He stated that he arrived before 1300 to start setting up the cameras for the dress rehearsal. At approximately 1300 hours, he and Scott Morgan went up to the attic area to look at the architecture. He stated they saw the two light fixtures that had been removed to suspend the lighting truss. He stated that he believed that one of them was laid on its side. He did not see whether they had lamps in them. He stated that the lights were not on at the time and the earliest time he could remember seeing the dimmable circuit on was at the start of the rehearsal at 1900 hours. He also stated there were two light trees in the east corners that were plugged into house power. Between 2100 and 2130 he smelled smoke. He commented over the headset that he smelled 30

39 something that smelled like dust burning off of lights. We asked him how long it took to burn the dust off of production lights and he said it usually happened within a short time of the lights being on, or once they were run up and down two or three times. When asked if smelling hot lights at this point in the dress rehearsal was unusual, he responded that it was. In the days following the interview with Mr. Bunton, FM Schofield got a Facebook message from an EMS colleague who indicated that another camera operator, Scott Morgan, may have a photo of the truss suspension system set up in the attic for the production. W-14 Scott Morgan Scott Morgan was the operator of Camera 1 in the center of the east balcony. He arrived prior to He and Brian Bunton went into the attic to look at the truss structure and architecture. They observed the suspension system for the lighting truss. Mr. Morgan took a photograph of the set up with his cell phone. Figure 27 is the photograph taken by Mr. Morgan. Figure 27: Lighting Truss Suspensions in Tabernacle Attic Photo Courtesy of Scott Morgan Mr. Morgan stated that it was difficult to identify the structures in the photograph, so he provided a second photograph with the structures labeled. Figure 28 is the picture as labeled by Scott Morgan. 31

40 Figure 28: Lighting Truss Suspensions in Attic with Diagram by Scott Morgan Photo Courtesy of Scot Morgan Mr. Morgan stated that he also smelled a dusty light odor at about When asked, he indicated that it would be unusual to have that type of an odor that late into a rehearsal. He stated that was why he and Mr. Bunton commented on it over the head sets, because it was, in his opinion, unusual. W-13 Paul Hopkins On December 22, 2010, FM Schofield was summoned to the perimeter fence by the security staff. Mr. Hopkins stated he had information that related to the fire in the Tabernacle. Mr. Hopkins indicated that he had seen what may have been smoke prior to the 0110 alarm on the morning of the fire. We obtained his contact information and set up an interview for December 30, Mr. Hopkins was interviewed at the Utah State Fire Marshal s Office on December 30, Mr. Hopkins stated that he was a courier who transports blood from the St. George area to Salt Lake City. On December 17, 2010, he was on his normal delivery route when he drove through Provo. He stated that he had to drop off some paint at the Sherwin Williams store on south 32

41 University Avenue. He indicated that he exited on University Avenue then dropped off the paint before continuing north on University Avenue, until he reached University Parkway where he turned west back to the interstate. He stated that he drove by the Tabernacle at approximately He stated that he saw a fog like haze on the east side. He stated he did not see the same haze on either the south or north sides of the building. He stated that the fog was illuminated in the floodlights. He stated that he did not see this haze anywhere else in Provo. He was asked if he had seen any other fog that evening and he stated that he had seen fog down by Fillmore. He then verified that he was in the area of the Tabernacle at approximately Cast Members There were approximately 100 people in the cast of the Gloria production. It was reported by the media that some of them stated they had smelled smoke during the dress rehearsal. FM Schofield contacted the cast members following a performance at the American Fork Tabernacle, again at the Utah Valley University LDS Institute, and at the Utah Valley University Special Events Center. The members of the cast were contacted by telephone and sorted, based on specific criteria. All but 12 of the cast members were contacted. It was determined that the odors they reported were most likely not associated with the origin and cause of fire, due to the locations they reported and the time they indicated that they smelled something unusual. Others Several other individuals were interviewed by investigators during the investigation. Their statements are used to corroborate information already contained in this report. These individuals included other members of the production crew and members of the general public who were present at the dress rehearsal. A complete list of witnesses is located in Appendix B. Building Construction Construction of the Provo Tabernacle began in the fall of 1882 and was completed in The exterior dimensions of the building are 88 feet wide (north to south) and 160 feet long (east to west). Each of the four corners of the building has an octagonal shaped turret that extends one story above the masonry wall. The foundation is stone and mortar with a center support wall extending the length of the building. The walls are unreinforced brick. The interior dimensions of the building are 64 feet wide by 126 feet long with a ceiling height of 44 feet 6 inches. The floor area is 8,064 square feet. A balcony lines three of the four walls and was supported by 18 iron columns. The original structure included a center tower; it was removed in 1919 because the roof was beginning to sag. Figure 29 shows the Tabernacle as it appeared prior to the fire. Figure 29: Aerial View of the Tabernacle Prior to the Fire 33

42 Photo Courtesy of Provo City Corporation Foundation The foundation of the Provo Tabernacle is stone and mortar. The exterior foundation walls are approximately 24 inches in width. There are also three interior foundation walls. Two walls run beneath the columns supporting the balcony, and one wall runs the length of the building. The two foundation walls beneath the balcony measure approximately 20 inches wide while the center foundation wall is approximately 24 inches wide. Exterior Walls The exterior walls are unreinforced brick and mortar. The walls are 5 wythes wide. Floor The floor structure is composed of 2 by 12 inch rough-cut lumber covered with one-inch tongue and groove planking. The wooden floor is carpeted. Balcony The balcony is supported by 2 by 12 inch rough cut joists inserted into the exterior walls on the outside and supported by 18 iron columns. The balconies are accessed by staircases located in each of the turrets. Figure 30 shows the balcony structure prior to the fire. Figure 30: Provo Tabernacle North Balcony 34

43 Photo Courtesy of BYU Broadcasting Ceiling The plaster ceiling consisted of 2 x 8 inch joists with 2 x 1/4 inch wooden lath. The lath had a one-quarter inch gap to facilitate the adherence of the plaster finish. The ceiling was suspended by iron rods from the truss structure of the roof. Prior to 1985, there was a system of catwalks throughout the ceiling to facilitate maintenance. In 1985 a plywood deck was installed, aluminum backed insulation was placed in the interstitial space, and the entire electrical conduit was run on top of the plywood deck. Where light fixtures were located, a 2 x 2 foot wooden box was constructed to keep the blown-in fiberglass insulation away from the light fixtures. An elevated walkway was placed on the ceiling deck to maintain the blown-in insulation. Roof Structure The roof of the Tabernacle consisted of 9 full trusses, 4 one-half trusses, and 8 truss braces. Figure 31 illustrates the main truss structure of the roof. 35

44 Figure 31: Diagram of Provo Tabernacle Roof Structure Each truss consisted of up to of up to 10, 2 x 12 rough-cut inch planks held together with iron bolts. Angled portions of the trusses that connected the top and bottom chord were interwoven into the structure of the truss. Figure 32 shows a portion of the truss structure. Figure 32: Provo Tabernacle Roof Truss 36

45 In 1985, 6 x 6 x ½ inch steel angle iron was added to the top chord of each of the main trusses to keep them straight. At some point in the buildings history, 1 1/2 inch iron rods were added to give strength to the roof structure. There was sufficient space to walk in the attic area beneath the center portion of the truss structure. The remodeling plan in 1985 called for the ceiling deck and the entire truss structure to be painted with two coats of intumescent paint, however, it cannot be verified what the fire resistive rating may have been or the useful life span of the fire protection feature. The roof deck of the Tabernacle consisted of 2 by 8 joists topped with plywood and cedar shakes. Electrical System The electrical service entered the building on the northwest wall of the west foyer. There are two main breaker panels on the main floor, a breaker panel located in the room above the west foyer, and smaller breaker panels in the north hall and the organ blower room. The system was completely encased in conduit. There had been some electrical upgrades over the years, but the extent is not known to investigators. HVAC The heating for the Tabernacle was provided by radiators throughout the building fed by a boiler located in the building to the west of the structure. Cooling was provided by chillers located in the attic space on either end of the building. The temperature was kept above freezing by an automatic thermostat. When the building was occupied the heating and cooling system was controlled in three hour blocks by a manual control. The manual control is what the security guard was asked to reset through out the night. Fire Protection 37

46 The Tabernacle had a smoke detection alarm system that was installed in There were smoke detectors located in the attic, turrets, and in the assembly area. The fire alarm control panel was located in the west foyer area. The detectors located in the attic were placed approximately 9-10 feet above the deck on the north side of the truss structures. They were located well below the peak of the roof. The alarm system was a local alarm to the building and not monitored offsite. According to the facilities maintenance group and other church employees and volunteers, the alarm system had a history of going into alarm for no apparent reason. The facilities maintenance group moved a detector from the attic to the west foyer to try and slow down the false alarms. The alarm system was tested on December 2, 2010 and it failed, due to poor detector sensitivity. A review of the inspection report indicates that the inspection may not be a complete or through inspection. The alarm testing report is included in Appendix C. The Tabernacle was not equipped with an automatic fire sprinkler system. Figure 33 illustrates the location of key electrical, HVAC, and fire protection system components. Figure 33: Fire Alarm Panel, HVAC Equipment and Electrical Breaker Panel Locations Breaker Panels Air Handling Units Fire Alarm Panel Not to Scale Area of Fire Origin Based on witness statements and observed fire behavior, the area of fire origin is determined to be in the attic space. This determination is made based on the following circumstance: First, the eyewitness account from the person who discovered the fire. The witness is a trained observer and his identification of the hole in the ceiling supports the attic as the area of origin. Second, the building s fire detection system went into alarm sometime between 2315 and The alarm panel identified the problem as being in the attic. Third, the fire behavior observed on scene indicates the fire started high in the building. Both the behavior of the smoke and the first flame observed from the exterior of the building indicated the fire was above the level of the ceiling. 38

47 In addition, a fire originating on the main floor would have been detected by the security guard at With the area of fire origin determined, a plan was developed to complete the necessary excavation of the structure. The focus, based on observed fire behavior and witness statements, was in the west half of the building with the area of the dimmable incandescent light circuit of particular interest. Building Excavation and Data Collection After completing the first round of interviews and reviewing the building plans, the Task Force identified the following list of specific items of interest: The Fire Alarm Panel The Dimmer Relay All Breaker Panels The 8 Dimmable Incandescent Can Light Fixtures Electrical Wiring and Conduit The Dimmer Connection the North Balcony The Dimmer Box As a courtesy to the property owner, the Task Force wanted to locate the following items to show proof of loss: The Minerva Taggert Painting The Tympani Drums The Fazioli Piano The Harp Jacobsen Construction began hazard mitigation and structural stabilization on December 20, The investigators were not able to do any site work on December 20 or December 21. On December 22, members of the Task Force entered the east end of the building to look for the Minerva Taggert painting to provide proof of loss. The remnants of the painting were found in the late afternoon. The remnants were marked, photographed, and diagramed. After the remnants were photographed, they were removed from the building, wrapped in plastic and turned over to Glen Johns Managing Director of Risk Management at BYU for transportation to the property owners for preservation. On December 28, 2010 investigators requested the UHP mini-helicopter to provide aerial photography of the structure. Those photographs were used to establish a grid pattern for our excavation and identify trends in fire behavior. The grid pattern developed for the excavation is shown in Figure

48 Figure 34: Grid Pattern for Tabernacle Site Excavation Photo courtesy of UHP and Provo City GIS The grid system was set up because of the information received from the witnesses and observed fire behavior. Based on the information to this point, it was determined that the focus of our excavation would be on the west side of the building. If during the course of our investigation the evidence supported additional excavation of the east side of the building, the grid would be reconfigured. A second identical grid system was established north of the building in the park. The grid was an exact footprint of the Tabernacle, rotated 90 degrees so that it would fit in the park. It was laid out on reinforced plastic sheeting. The investigators also had a small sheet staked out for the items that represented proof of loss. A section of a steel container was reserved for items of evidence. These steps, combined with the videography and photography of the excavation were taken to mitigate any claim of spoliation of evidence. On January 3, 2011 the Task Force began our excavation of the Tabernacle. The excavation would take until January 21, The following is a summary of the relevant data found during the excavation. General Observations The excavation began from the north middle door. The south door was still being stabilized. Each of the grids were marked and numbered. The east side of the building appeared to have been more consumed by the fire than the west. The roof trusses on the east had large sections that were so completely consumed that all that remained was the 6-inch angle iron bracing. It would be difficult to differentiate what portions of the trusses burned prior to the roof collapse and what was consumed by the continued fire once the roof had collapsed. The investigators 40

49 located some charred remains of the wooden pews near the east entrance, and then moving west found an increase in the remaining debris. Sections of the roof deck, complete with wooden shakes were identified as were sections of ceiling deck with wooden lath and plywood intact. Two large air handling units and piping for the steam heat were located, as were several crushed air ducts that were also noted. The Task Force was not able to access the west foyer where the breaker panels were located, because there was approximately 11 feet of debris at that location. They were able to access the choir loft, although further inspection showed the floor beneath had been mostly burned away. During the inspection of the choir loft area, we noted that some of the chairs still had the foam padding intact on the seats. We also noted there was a large area of the stage that had either burned or broken through and collapsed down to the dirt level. It was concluded that this was the stage area where the first fire in the Tabernacle had been discovered. It is anticipated that this was the general area where we would find the instruments that were left in the building overnight, as well as the lighting truss. This information provided the task force with a general direction to begin the excavation of the shell. Because of the amount of debris, it was necessary to remove the roof structure from the shell prior to excavating what we considered to be the area of fire origin. Figure 35 illustrates some of the large items of debris as it presented on January 3, Figure 35: Large Debris Items Located in the Interior NW ½ Truss Remains of Trusses 1-5 Air Handling Unit Air handling unit Roof Deck with Shakes S.E. Truss Brace SW ½ Truss Photo courtesy of UHP 41

50 Site Excavation As the excavation of the large debris was initiated, some of the trusses had to be cut in half to enable the cranes to lift them out of the shell and place in the alternate grid. As work continued to the west, investigators identified sections of roof complete with the cedar shakes. Sections of the plywood ceiling deck were also identified. There were piles of brick from the gable sides that were pulled in during the second roof collapse. Jacobsen Construction provided two crews of laborers to assist in removing the debris. As investigators systematically removed the debris, one crew would rig the piece or section for removal while the other crew salvaged bricks. As each piece of debris was removed, it was marked, logged, and then guided into place on the outside grid by a member of the Task Force. As the roof structure was removed, Investigators Mills, Peterson, and Schofield made access underneath the west end through an office window. From the office they were able to move under the choir loft into the west foyer where they identified the house light switches, the fire alarm control panel, two dimmer racks, and the remains of the fire alarm horn. The dimmer control for the Tabernacle system was found in the office. It is shown in Figure 36. Figure 36: In-House Tabernacle Dimmer Control Box Photo by L. Schofield 42

51 After the majority of the roof structure had been removed, investigators began to excavate in the area of fire origin as identified by the witness. The initial excavation was in the pit area, where the front stage used to be. To give perspective to the area of the initial excavation, reference Figure 37. Figure 37 is a photograph taken on December 16, This will provide a background for the excavation of the area of origin. Figure 37: Physical Layout of the Tabernacle December 16, 2010 Lights set aside to suspend lighting truss Dimmable Incandescent Light Circuit Light Truss Choir Loft Rostrum Area Elevated Stage Photo courtesy of Tyler Weston 43

52 Figure 38 illustrates the stage areas and choir loft after the fire. Figure 38: Physical Layout of the Tabernacle After Removal of Large Debris Choir Loft Rostrum Area - Burned Through into Crawl Space Elevated Stage N Photo by T. Mills As debris was removed, investigators were able to access the area below the elevated stage and the rostrum area and identify items of interest, including light fixtures and instruments. They also observed that many of the floor joists on the south side had been broken presumably when the roof collapsed. As the excavation continued, large structural debris was removed and burn patterns were noted on the structural members. Investigators were then able to begin locating items of particular interest. Figure 39 shows the locations in the grid of items associated with the suspended lighting truss. They include the 10 gauge yellow extension cord, both chain crawlers, and sections of both the square and triangular trusses. It is important to note, that most of the truss pieces and associated gear were found very close to the north and south midline of the building. A more in depth discussion of items found will occur during the analysis of the excavation. The identified locations of truss debris are not all inclusive. There were other items found such as light motors, gel frames, and assorted wiring and cabling that were identified, but not included in this report. 44

53 Figure 39: Location of Recovered Items Associated With the Lighting Truss N Not to Scale The items associated with the dimmable incandescent lighting circuit are shown in Figure 40. They include: light fixtures, associated conduit, reflective light housings, and associated wiring. Figure 40: Location of Recovered Items Associated with Incandescent Lights N Not to Scale 45

54 On January 14, 2011, a reflective bell was uncovered in Grid Section 2. This reflective bell was significant, because it had areas that had been thermally damaged while the light was in an upright or nearly upright position. The Task Force completed the excavation of the shell on January 20, Provo Fire & Rescue turned custody of the property over to the property owner on Friday, January 21, 2011 at 1900 hours. Origin and Cause Determination The origin and cause determination was made using the scientific method as defined in NFPA 921 Guide for Investigating Fire and Explosions. The seven steps are 1. Recognize the need. ( Identify the Problem (NFPA ) a. A fire occurred in the Provo Tabernacle 2. Define the problem (NFPA ) a. What are the circumstances, conditions, or agencies that brought about or resulted in the fire at the Provo Tabernacle 3. Collect Data (NFPA ) a. Witness statements, observed fire behavior, physical evidence 4. Analyze the data (NFPA ) 5. Develop a hypothesis (NFPA ) 6. Test hypothesis (NFPA ) 7. Select final hypothesis This investigation was completed using the NFPA 921 Guide for Investigating Fire and Explosions as the reference standard. As the analysis was completed, the following definitions apply from NFPA 921. Origin 1. Area of Origin. The room or area where a fire began. (NFPA ) 2. Point of Origin. The exact physical location where a heat source and a fuel come in contact with each other and a fire begins. (NFPA ) Cause 1. Arson. The crime of maliciously and intentionally, or recklessly, starting a fire or causing an explosion. (NFPA ) 2. Cause. The circumstances, conditions, or agencies that brought about or resulted in the fire or explosion incident, damage to property resulting from fire or explosion incident or bodily injury or loss of life resulting from the fire or explosion incident. (NFPA ) 3. Fire Cause. The circumstances, conditions, or agencies that bring together a fuel, ignition source, and oxidizer (such as air or oxygen) resulting in a fire or combustion explosion. (NFPA ) 4. Proximate Cause. The cause that directly produces the effect with out the intervention of any other cause. (NPFA ) 5. Accident. An unplanned event that interrupts and activity and sometimes causes injury or damage of a chance occurrence arising from unknown causes: an unexpected happening due to carelessness, ignorance and the like. (NFPA ) 46

55 6. Incendiary Fire Cause. A fire that is intentionally ignited under circumstances in which the person knows that the fire should not be ignited. (NFPA Other Definitions 1. Drop Down. The spread of fire by the dropping or falling of burning materials. Synonymous with fall down. (NFPA ) 2. Glowing Combustion. Luminous burning of a solid material without visible flame. (NFPA ) 3. Heat of Ignition. The heat energy that brings about ignition. (NFPA ) 4. Ignition Temperature. Minimum temperature a substance should attain in order to ignited under specific test conditions. (NFPA ) 5. Ignition Time. The time between the application of an ignition source to a material and the onset of self-sustained combustion. (NFPA ) 6. Material First Ignited. The fuel that is first set on fire by the heat of ignition: to be meaningful, both a type of material and form of material should be identified. (NFPA ) 7. Ventilation-Controlled Fire. A fire in which the heat release rate or growth is controlled by the amount of air available to the fire. (NFPA ) 8. Venting. The escape of smoke and heat through openings in a building (NFPA ) The first step in the data analysis was to determine the area of origin. After reviewing witness statements, and observed fire behavior through photographs, video recordings, and burn pattern analysis it was determined that the area of origin is in the attic space, directly above the elevated platform as identified in Figure 41. Figure 41: Provo Tabernacle Ceiling Joist Layout with Area of Fire Origin Area of Fire Origin N Not Not to to Scale Scale 47

56 This was determined to be the area of origin for the following reasons: First, the last person in the building, W-1 Williams, provided the Task Force with the location of the fire on the stage and the hole with two layers of fire in the ceiling. It was concluded that his information was specific and credible. Second, there was a fire alarm in the attic between 2315 on December 16, 2010 and 0110 on December 17, 2010 that initiated in the attic space according to the fire alarm panel. Third, when W-1 Williams entered into the building at 0110, he did not observe or smell any fire. The only observation that he made in clearing the building for intruders that we believe was associated with the fire, was the popping and crackling sounds he heard while up in the northeast balcony. Fourth, the observed fire behavior indicates that the fire was in the attic space. Figure 42 shows the venting observed by the first arriving firefighters. Figure 42: Initial Presentation of Smoke Conditions Note the smoke from the soffit and the light smoke coming from the upper level window. Note the black smoke venting out of the gable vent and soffit. Note that there is no smoke observed venting from any of these windows, or any of the turret windows. Photo courtesy of A. Williams As is illustrated in Figure 42, the smoke level inside of the building is above the level of the top windows. There is enough smoke present in the attic to vent out of the soffits and gables. It should also be noted, that the smoke venting out of the gable vent and soffit as identified in Figure 42, is black in color indicating incomplete combustion. This is also an indication this is a ventilation-controlled fire. Another indication that this was a ventilation-controlled fire in the attic space occurred when the windows failed. Figure 43 shows the first visible fire after the windows failed. 48

57 Figure 43: Visible Flames and Increased Smoke Turbulence Note the flames are all in the top ½ of the window. The flames are pushing down into the assembly area where the air is. Photo courtesy of A. Williams The first observed flames were pushing out of the attic space into the assembly area. There are two reasons for this fire behavior. First, the flames are travelling the path of least resistance. The roof deck has not failed at this point, so the fire was confined in the attic space until the ceiling failed. The entry crew was not able to see the fire in the attic as the smoke level was dropping below the ceiling level. Second, this fire is ventilation controlled. Once the fire had enough oxygen drawn into the attic space, free burning resumed with the fire pushing out the bottom of the ceiling into the assembly area following the source of oxygen. Figure 44 illustrates the flame spread from the attic into the assembly area. 49

58 Figure 44: Visible Flames Pushing Down From the Attic Note the level of the flames, high in the ceiling, not moving to the window Note the heavy black smoke pushing from the windows. This is an indication of incomplete combustion and a ventilationcontrolled fire Photo courtesy of Tree Gore Finally, the west section of roof collapsed at approximately 0440 just two hours after the fire was discovered. As a rule of thumb, a heavy timber roof structure should be able to sustain fire impingement for long period of time. Based on this data and our experience, the Task Force has concluded that the fire originated in the attic space. There may be concern about the fire that W-1 Williams observed on the stage. Investigators have concluded that the fire on the stage was the result of a drop down fire from the attic space. The following data supports this conclusion: First, when W-1 Williams observed the fire on the stage he described the flames as being two to three feet in height. He also stated that the fire had not yet extended into the choir loft. When the fire department entered the structure a few moments later, they observed the flames to be 20 feet in height and extending into the choir loft. Second, it is unlikely that a fire in the assembly area could produce the fire conditions and behavior observed by the first in units. In addition, it is highly improbable that a fire that originated in the assembly area could generate enough of a heat release rate, to perforate the ceiling and burn enough of the heavy timber trusses to cause a roof collapse in less than two hours. 50

59 Point of Origin The witness statements, observed fire damage, and data collected in the excavation of the building, place the point of origin inside of the dimmable incandescent light circuit. Cause Heat Source Placed too Close to a Combustible Object The probable precipitating events were the two incandescent light fixtures that were set aside to suspend the light truss. These two fixtures were placed in contact with the top of the wooden speaker enclosure. According to witnesses, these lights were equipped with a Sylvania model 300BR40/FL lamp. W-5 Crane indicated that if the lights were set aside to suspend an object, the star for example, the fixture would have to be disarmed or there would be a fire. The packaging on the bulb reads: Due to high temperatures do not allow paper or other flammable or heat sensitive materials within 12 inches of the glass bulb during operation. When asked if he had removed the bulbs from the fixtures when he set them aside to suspend the truss, W-2 Ostler stated that the fixtures were not connected. Later in the same interview, he stated the lights had a 2 foot flexible metal conduit and the wiring was connected by wire nuts. In a subsequent interview, he stated there were no lamps in the fixtures, because they were light as a feather. W- 2 Ostler never asserts that he either looked at, or disarmed, either of the light fixtures that were set aside to suspend the light truss. The speaker enclosure and any adjacent ceiling deck and joists would have been extremely dry and the development of self-sustaining combustion would be certain, if it came into contact with a sustained heat source capable of raising the material to its ignition temperature. There were no other potential fire causes located in the area of fire origin. Figure 45 shows the complete dimmable incandescent light system. Figure 45: The Dimmable Incandescent Light Circuits Fixtures part of the six light circuit. These were removed to suspend the light truss These are the South side of the six- light circuit These are the North side of the six-light circuit Lights over the choir conductor and podium. They are on a separate circuit Photo courtesy of the Church of Jesus Christ of Latter-day Saints 51

60 Trax Lighting and AV set aside the east incandescent lights to suspend the light truss. The remaining lights were used in the lighting scheme for the production and are readily seen in both video footage and still photography from the dress rehearsal. The incandescent lamps that were set aside were placed bell down onto the wooden speaker enclosure and ceiling. The incandescent lights are attached via a flexible metal conduit approximately two feet in length. They have previously been lifted up to change the lamps, or on occasion, suspend some object from the ceiling. Two weeks prior to this fire, the lamp over the conductor s area, which is not a part of the same circuit as the lamps set aside to suspend the lighting truss, was removed to suspend a star as a part of a live nativity scene held in the building. Hypothesis Development After reviewing the information received from witnesses, observed fire behavior, and the evidence gathered during the excavation of the structure, the Task Force has narrowed the focus to two hypotheses. First, that a heat source, specifically an incandescent light fixture with an energized 300 watt bulb, will generate enough heat to bring the plywood deck and/or structural members of the ceiling deck to their ignition temperature resulting in self-sustaining combustion. The Task Force developed a plan to test this hypothesis. Hypothesis Testing Hypothesis 1 The hypothesis is that a heat source, specifically an incandescent light fixture with an energized 300 watt lamp, placed too close to combustible materials, is a legitimate proximate cause of the fire at the Provo Tabernacle reported December 17, Rationale The rationale for this hypothesis is three-fold. First, in interviews with Jeremy Ostler, from Trax Lighting and AV, the status of the incandescent lights removed to suspend the lighting truss has never been clarified. He has stated that the fixtures were not wired at all, and then in the same interview, he stated the fixtures were tethered with a flexible metal conduit connected with wire nuts. Mr. Ostler also stated that this circuit was in use during the rehearsal. Second, there has never been an affirmative statement by Mr. Ostler that he removed the lamps from the two incandescent fixtures that were set aside to suspend the lighting truss. In his statements to investigators, he stated there were no lamps in the fixtures in the first interview and then in a subsequent interview, he stated that he did not believe there were lamps in the fixtures because they were as light as a feather. These statements are contrary to four other witnesses, with extensive knowledge of the building, that state unequivocally that all of the incandescent light fixtures had working lamps, with the exception of the northeast incandescent light that was burned out. And finally, all light receptacles found during the excavation had lamp bases intact. Third, there was thermal damage to the southeast incandescent light fixture indicating a high level of heat. The fixture was confirmed as one of the two fixtures removed to suspend the lighting truss by a person with extensive knowledge of the building. The fixture showed signs of melting at the top of the bell that would have occurred while the bell was in an upright or nearly upright position. 52

61 Research Questions 1. Does the light fixture in question, with the lamp used in the dimmable incandescent system, generate enough heat to create self-sustaining combustion? 2. Will the plywood decking, if heated to an ignition temperature, provide an adequate fuel source to originate and sustain combustion? 3. What impact does the presence of aluminum-backed fiberglass have on fire spread? 4. Will the reflective bell on an incandescent light generate enough heat when placed in an upright position on a plywood platform; melt the insulation on a light fixture causing a fault that will trip the circuit breaker? Test Set-Up Permission was received from Utah Fire & Rescue Academy to use their burn building to test the hypothesis. Permission was also received from the LDS Church, Gordon Hansen from Case Forensics, and Dennis Jones from Burn Pattern Analysis to use a section of unburned ceiling deck. Consent was given, and a piece of plywood from the ceiling deck was obtained and secured in the Provo Fire & Rescue Airport Station to allow it to dry out. Because of spoiliation concerns, a light fixture from the debris field was not able to be used. The dimensions of the reflective bell for the light fixture in question were measured. As an exact replica was unable to be obtained, one was manufactured using the acquired dimensions. The lamp from the Provo Facilities Maintenance group was obtained. They were able to go back into their records and obtain the same lamp used in the dimmable incandescent light circuit. Assumptions and Limitations Assumptions It is assumed that the testing will not be an exact replication for the following reasons. 1. The plywood had been sheltered in the attic space since That means that the plywood was extremely dry. During the suppression operations, a significant amount of water was put into the debris field. In addition, on December twelve inches of snow fell onto the debris field. Additional snow fall accumulated during the month of January. It is assumed that the plywood inside of the attic space would combust more quickly when exposed to a heat source. 2. All structural members of the ceiling structure were rough cut and over 130 years old. It is assumed that the structural members would combust more quickly when exposed to high temperatures. 3. The fiberglass used would respond similarly to the original aluminum-backed fiberglass batting installed in Investigators were not able to locate any aluminum-backed fiberglass batting. 4. It would be assumed that the plywood would have been intact. 53

62 Limitations 1. The plywood used had been exposed to high temperatures, inclement weather, and the collapse of the roof structure. The testing may be limited by structural changes, as a result of the above-mentioned items. 2. Investigators were not able to locate 130 year-old rough cut lumber that had not been exposed to any weather. Off the shelf lumber was used. 3. Investigators did not have the ability to use plaster. One and ¼ inch lath was purchased. The lower part of the ceiling structure was covered with ½ inch gypsum board. 4. Investigators were unable to locate the exact light fixture used in the Tabernacle. A mock-up was fashioned, using the dimensions from fixtures found in the Tabernacle and using the same materials. Test Procedure The test was conducted as follows. DFM Adams constructed two boxes using finish cut two by eights. The boxes were 16 inches wide, 4 feet long and 8 inches deep. The bottom of the box was covered with one-quarter inch by two-inch slats simulating lath. The sides, bottom, and ends of the box were enclosed by one-half inch dry wall. The boxes were labeled for identification. Mock-Up #1 was filled with fiberglass insulation. Because no aluminum backed insulation is available, a layer of aluminum foil was placed over the top of the fiberglass. The plywood deck was then attached using six-penny nails. Mock-Up #2 was not filled with insulation. Investigators were unsure whether all of the void spaces had fiberglass batting, so it was decided to test with and without fiberglass. Figure 46 shows one of the mock-ups. Figure 46: Mock-Up Box Construction grounded plug. Once the lids were attached, the boxes were placed across four 2 x 2 inch boards suspended between two saw horses in the burn room. As previously mentioned, investigators were not able to obtain the exact replicas of the light fixtures in question. The Task Force obtained two 11- inch aluminum bells from commercially available clamp lights, and then placed a three and one-quarter strip of rolled tin around the inside to provide more depth. The bell opening is 10 inches across. The rolled tin was fastened with pop rivets and all openings and connections were sealed with silver high-temperature duct tape. The light bases were ceramic in composition and were attached to 14- gauge pigtails that terminated at a three prong, 54

63 The power feed to the system was a 12-gauge electrical cord wired directly to a 20-amp circuit breaker. The main power terminated in a grounded three-prong female end, and a 10 gauge 3- wire, three-prong outlet pigtail connected the light fixtures to the power source. Figures 47 and 48 show the light fixture used for this hypothesis testing. Figure 47: Light Fixture Lamp Figure 48: Light Fixture Profile 55

64 The boxes were monitored for heat utilizing an Amprobe TMD-10 Dual Temperature Meter with 2 Type K (-328 degrees Fahrenheit to 2498 degrees Fahrenheit) thermocouples. One thermocouple was placed into the interstitial space and the second was placed directly under the bell of the light fixture. Temperature readings on the exterior of the reflective bell were taken using a Ryobi heat-sensing gun. The entire testing sequence was recorded using timed still pictures and videography. Figure 49 illustrates the testing set up. Figure 49: Testing Set Up The Test At 1057 hours, the lights placed on the mock up decks were energized. Temperature readings were taken and recorded. Figure 50 represents the readings taken from Mock- Up #1 that contained insulation. 56

65 Figure 50: Mock-Up #1 Data Mock-Up 1 Temperature Production Degrees Farhenheit External Probe Interstitial Probe Bell Exterior Time in Minutes The temperature readings from Mock-Up #2 are recorded in Figure 51 Figure 51: Mock-Up #2 Data Mock-Up 2 Temperature Production Degrees Farhenheit Bell Temp Interstitial Probe External Probe Time in Minutes As is illustrated, the incandescent lamp generates sufficient heat to cause combustion of the plywood decking. The significant differences noted between the two boxes are primarily the result of insulation in the interstitial space. The insulation reflected much of the heat back to the decking. Because of the reflected heat, the surface temperature of the plywood decking rose faster than in Mock-Up #2. In Mock-Up #2, the heat dissipated in the interstitial space causing the surface temperature to rise more slowly than in Mock-Up #1. It also took substantially longer to burn through the plywood deck in Mock-Up #2. 57

66 It was anticipated that once the plywood decking burned through, there would be an increase in the rate of combustion up to, and possibly including, free burning. Once the decking burned through, there was an increase in combustion as evidenced by a shortterm increase in smoke production. However, in the nearly six and one-half hours that Mock-Up #1 spent under an energized incandescent fixture, free burning with flame was never observed. Figure 52 illustrates the pyrolysis achieved in Mock-Up #1. Figure 52: Mock-Up #1 300 watt energized light fixture similar to the one in the attic Glowing embers indicative of sustained combustion Note the symmetrical pattern of the burn through the plywood Test Instrument It took much longer for Mock-Up #2 to obtain ignition temperature. Once the deck had burned through, the heat continued to dissipate into the interstitial space. Figure 53 illustrates the pyrolysis that occurred on Mock-Up #2. 58

67 Figure 53: Mock-Up #2 300 Watt energized light fixture similar to the one in the attic Burning ceiling deck after heat source is removed Note the symmetrical pattern of the burn through the plywood External thermocouple Test instrument Interstitial Thermocouple After observing the behavior in the testing of Mock-Up #1 and 2, investigators discussed the observable results and determined that while the testing had affirmed the hypothesis, to this point, a different set up was required. It was determined that a change in the fuel set up was indicated. At this point, testing was discontinued on Mock-Up #2 and an additional research question was added. Research Question Five What would the effect be, if an incandescent fixture with an intact and energized lamp were placed on a plywood deck with a ceiling joist or dimensional lumber beneath it? The rationale for this additional question is three-fold. First, although testing has confirmed combustion, the speed at which the combustion was taking place raised concern as to whether it could spread with sufficient speed to produce the observed fire behavior in the early hours of December 17, Second, many of the pieces of the ceiling debris removed from the Tabernacle had joists or two-inch cleats attached. The cleats were placed in 1985 when the plywood decking was installed. Third, because the incandescent light fixtures were enclosed in boxes to keep the blown-in insulation away and the fixtures had a relatively short tether, it is possible, if not probable, that when the 59

68 lights were placed on the plywood deck they would be over a portion of dimensional lumber. The plywood deck of Mock-Up #2 was removed and the box was cut in half and then a piece of 2 x 8 lumber was inserted in the middle to simulate a joist or piece of dimensional lumber. Insulation was placed into the interstitial space and covered with aluminum foil. The thermocouples were reset and then investigators replaced the plywood deck. Figure 54 shows Mock-Up #3. In the photographs, Mock-Up #3 is labeled as 2a. Figure 54: Mock-Up #3 Mock-Up #1 Energized 300 watt incandescent light fixture similar to those in the attic Test Instrument Amprobe Approximate center line of joist The light fixture was placed on the plywood decking with approximately one-fourth of the fixture over the joist. The lamp was energized and temperature readings were obtained. Figure 55 represents a graphic representation of the temperatures obtained over the span of the test. 60

69 Figure 55: Temperature Production in Mock-Up #3 Mock-Up 3 Temperature Production Degrees Farhenheit Exterior Temp Intersititial Temp Bell Temp 0 Minutes Time in Minutes Unlike the previous two tests, once the deck reached combustion temperature and began to produce smoke, the rate and character of smoke production continued to increase until the conclusion of the test. After two hours and fifteen minutes under the energized fixture, we removed the light fixture to observe the pyrolysis on the plywood deck. Figure 56 shows the state of pyrolysis when the energized light fixture was removed. 61

70 Figure 56: Mock-Up #3 with Combustion 300 watt nonenergized light fixture similar to those found in the attic Note the asymmetrical pattern of the burn-through. Charred 2 X 8 floor joist Test Instrument Stop Watch Inspection of the area under the light fixture showed continuing combustion, as evidenced by continued smoke production and red glowing embers. Closer inspection showed charring of the joist with red glowing coals at the joist. Figure 57 shows the selfsustaining combustion occurring in Mock-Up #3. 62

71 Figure 57: Mock-Up #3 Self-Sustaining Glowing Combustion Note the asymmetrical fire pattern. This indicates a different combustion pattern than displayed in Mock-Up #1 and Mock-Up #2 Once air was introduced with a very small breeze, free burning began. The production of flame was photographed. Figure 58 shows the onset of free burning. Figure 58: Mock-Up #3 Flaming Combustion 63

72 Mock-Up #3 was removed from the burn building and the plywood deck was removed. Figure 59 shows the interior of Mock-Up #3. Figure 59: Interior of Mock-Up #3 The insulation was removed and the depth of char on the truss was observed. This is illustrated in Figure 60 Figure 60: Char Depth in Mock-Up #3 Smoke staining and initial pyrolysis The red ember shown here indicates selfsustaining combustion is still occurring 64

73 The char level measured three and one-quarter inches. As is shown in Figure 60, the joist is still burning. A red ember is illustrated. In addition, smoke staining and charring is noted on one of the 2 x 8 side pieces up near the deck. Results The results of our testing of the stated hypothesis have produced the following answers to the research questions. 1. Does the light fixture in question, with the lamp used in the dimmable incandescent system, generate enough heat to create self-sustaining combustion? In each of the tests, the incandescent light fixture with an intact and energized 300- watt lamp produced sufficient heat to initiate a self-sustaining combustion. Although flaming combustion was only achieved in the third test, each previous test produced burning embers. The stated hypothesis is supported by the data collected in research question Will the plywood decking, if heated to a high temperature, provide an adequate fuel source to originate and sustain combustion? In each of the tests, the plywood decking provided sufficient fuel to originate and sustain combustion. The exact conditions present at the time and point of origin, in the evening hours of December 16, 2010 within the attic space of the Provo Tabernacle are unknown. What can reasonably be deduced from the data produced and the knowledge of construction present in the attic space, is that the plywood deck had been in-place-sheltered from the elements and dried in the summer heat for the past 25 years. Therefore, the stated hypothesis is supported by the data obtained in response to research question What impact does the presence of aluminum-backed fiberglass have on fire spread? The presence of fiberglass in the interstitial space reflected the radiant heat back to the plywood decking as evidenced by Mock-Up Number 1. This allowed for a faster burn-through of the ceiling deck. In terms of fire spread on the ceiling deck, the presence of insulation is of negligible value. In Mock-Up Number 2, the absence of insulation significantly slowed the speed of burn-through in the ceiling deck. As the heat radiated through the plywood deck, it dissipated into the interstitial space. There was an initial consideration that the absence of insulation would increase the amount of air movement when burn-through was accomplished, increasing combustion and fire spread; however, the test results did not support that theory. Finally, in the testing of Mock-Up #3 the role of insulation was clarified. In this test, the insulation reflected the heat back to the plywood decking as it had in Mock-Up Number 1. 65

74 In addition, the insulation allowed the heat to remain focused into the joist as opposed to dissipating into the interstitial space. Therefore, our testing supports the presence of insulation in the interstitial space as a factor in ignition and fire spread. We are led to conclude that the presence of insulation is at least partially responsible for the shape of the hole in the ceiling observed by Mr. Williams. Further testing is necessary to confirm this theory. 4. Will the reflective bell on an incandescent light generate enough heat, when placed in an upright position on a plywood platform, to melt the insulation on a light fixture resulting in a circuit breaker tripping? The power was fed from a 20-amp circuit breaker. When the lights were energized, they drew 2.5 amps of power through the system. The light on Mock-Up #1 was on from 1057 until The highest temperature recorded at the bell was 300 degrees Fahrenheit. The bell did get hot enough to melt a portion of the wire nut that was lying in direct contact with the bell. However, during the entire test the insulation on the wires did not melt nor did the breaker trip. 5. What would happen if an incandescent fixture with an intact and energized lamp similar to those in the Tabernacle was placed on a plywood deck with a ceiling joist or dimensional lumber beneath it? As with each of the previous tests, the plywood decking was sufficient to initiate combustion when the energized light fixture was placed on it. The difference was when the joist became superheated; it began the process of pyrolysis and created a more significant fuel source to sustain combustion. The burn pattern on the plywood decking showed fingers of combustion that were not symmetrical. This leads us to conclude that the fire inside the decking would have extended out past the border of the incandescent bell housing, resulting in a source of air that would increase combustion and ultimately lead to free burning. Once free burning is achieved, it is likely to continue until the fire runs out of air, or fuel, or heat, or the fire is suppressed. Conclusion Based on the testing completed February 22, 2011, the stated hypothesis that a heat source, specifically an incandescent light fixture with an energized 300-watt lamp placed too close to combustible materials, is supported as the cause of the fire at the Provo Tabernacle. 66

75 Hypothesis Test 2 Hypothesis A fuel source when heated to its ignition temperature and in a glowing combustion will continue to combust until it runs out of fuel, does not have sufficient oxygen to sustain combustion, or is suppressed. Rationale The rationale for this hypothesis is based on the fire behavior observed at the Provo Tabernacle on December 17, According to the eyewitness who discovered the fire, a very distinctive 10 x 20 foot hole was found in the ceiling. Testing confirmed the first hypothesis concerning a potential ignition source. The second part of the question is whether the self-sustaining combustion shown in Hypothesis 1 could create a similar burn pattern to the one observed by the witness. Research Questions 1. Will a fuel source, when heated to its ignition temperature, produce sufficient heat to initiate combustion in other fuel sources while inside of a confined environment? 2. Is it possible for a fuel heated to its ignition temperature to continue self-sustaining combustion horizontally, underneath insulation? 3. Is it possible that the self-sustaining glowing combustion observed during the testing of Hypothesis 1, create a hole similar to the one observed on December 17, 2010? Test Set-Up Consent was received from the LDS Church, Gordon Hansen of Case Forensics, and Dennis Jones of Burn Pattern Analysis, to secure four 2 x 8 inch rough cut ceiling joists from the debris pile at the Tabernacle. Plywood from the ceiling deck already in our possession was also used, as was one of the lights from the first hypothesis test. Assumptions and Limitations Assumptions It is assumed that the testing will not be an exact replication of the fire at the Tabernacle for the following reasons. 1. The plywood had been sheltered in the attic space since That means that the plywood was extremely dry. During the suppression operations, a significant amount of water was put into the debris field. In addition, on December twelve inches of snow fell onto the debris field. Additional snow fall accumulated during the month of January. It is assumed that the plywood inside of the attic space would combust more quickly when exposed to a heat source. 2. All structural members of the ceiling structure were rough cut and over 130 years old. It is assumed that the structural members would combust more quickly when exposed to high temperatures. 67

76 3. The fiberglass used would respond similarly to the original aluminum-backed fiberglass batting installed in Any aluminum backed fiberglass batting could not be located. 4. It would be assumed that the plywood would have been intact. Limitations 1. The plywood used had been exposed to high temperatures, inclement weather, and the collapse of the roof structure. The testing may be limited by structural changes, as a result of the above-mentioned items. 2. One-quarter inch lath cut was purchased off-the-shelf and the lower part of the ceiling structure was encased with ½ inch gypsum board instead of plaster. 3. The exact light fixture used in the Tabernacle was unable to be located. A replica had been fashioned using the dimensions and similar materials found in the Tabernacle. 4. The light fixture had been previously used for 8 hours during the testing of Hypothesis 1. It is unknown whether previous use would change the amount of heat produced. 5. Because the light fixture had been used in previous testing, a layer of creosote had built up on the interior of the reflective bell that may have altered the amount of heat being reflected back to the ceiling deck. Procedure The test was conducted as follows. DFM Adams created a mock-up using 2 x 8 rough cut lumber retrieved from the debris pile. The box had three joists, two on each side and one that ran down the center of the box. A 2 x ¼ inch lath was purchased and placed on the bottom of the box. The bottom was covered with ½ inch gypsum board. Aluminum foil was placed over the lath followed by insulation. Finally, the deck was attached. A light fixture was then placed over the center joist and energized. The light fixture had the same dimensions as the fixtures in the Tabernacle. The lamp is a Sylvania 300-watt flood lamp. Figure 61 shows the testing set up on Mock-Up #4. 68

77 Figure 61: Mock-Up #4 Set Up Photo by L. Schofield The Test The light was energized and the platform was brought to its ignition temperature. It took approximately two hours to establish glowing combustion as demonstrated in Figure

78 Figure 62: Mock-Up #4 Self-Sustaining Glowing Combustion 2 x 8 Joist heated to its ignition temperature and in glowing combustion Note the asymmetrical burn pattern Photo by L. Schofield Figure 62 confirms that the structural joist has been ignited using only the light fixture and lamp in questions. A small flame is visible; however flaming combustion was not sustained. Figure 63 shows the mock-up with only glowing combustion 70

79 Figure 63: Mock-Up #4 Self-Sustaining Glowing Construction 2 x 8 rough cut ceiling joists Note the asymmetrical burn pattern Note the glowing combustion Photo by L. Schofield The mock-up was then left to continue the test. When FM Schofield returned the following morning significant changes had occurred. The center joist that was initially ignited by the light fixture and lamp was completely burned away as was the lath and one end piece. The gypsum board and remaining joist collapsed on to the floor. Figure 64 and 65 illustrates the mock-up after the burn. 71

80 Figure 64: Mock-Up #4 After 10 Hours of Glowing Combustion Photo by L Schofield Figure 65: Mock-Up # 4 After 10 Hours of Glowing Combustion Remaining lath. The rest has been burned away Photo by L. Schofield 72

81 Results The results of testing this portion of the hypothesis have provided the following answers to our research questions. 1. Will a fuel source, when heated to its ignition temperature, produce sufficient heat to initiate combustion in other fuel sources while inside of a confined environment? Hypothesis Test 2 shows conclusively that sufficient heat can be conducted in a confined compartment to raise other fuel sources to their ignition temperatures. In this particular instance, the lath and each of the joists ultimately were raised to their ignition temperature and combusted. 2. Is it possible for a fuel heated to its ignition temperature to continue self-sustaining combustion horizontally underneath insulation? As demonstrated in Figures 64 and 65, it is possible for glowing combustion to continue underneath insulation. It is unclear what role the aluminum backing played on the fire spread, however, each of the pieces of lath were completely consumed to the bottom of the joist. 3. Is it possible that the self-sustaining glowing combustion observed during the testing of Hypothesis 1, create a hole similar to the one observed on December 17, 2010? Again, this test shows that it is possible to create this type of hole. It is possible that the wooden lath, once ignited, carried the fire under the ceiling joists causing them to combust. The hole would be opened when either the joists or lath were sufficiently weakened and could no longer support the plaster load. Evidence from the site excavation supports this, as debris including the triangular truss, chain motors, and light fixtures were all found closer to the center of the structure than expected. It can be deduced that when the ceiling fell, the flap swung from south to north based on the location of debris. Conclusion Based on this testing completed March 3, 2011, the stated hypothesis that a fuel source when heated to its ignition temperature and in a state of glowing combustion will continue to combust until it runs out of fuel, does not have sufficient oxygen to sustain combustion, or is suppressed is supported. In addition, the possibility of a combusting rectangular hole in a ceiling secondary to a heat source, specifically an incandescent light fixture, with an energized 300-watt lamp, placed too close to combustible materials, is supported as an extension of the legitimate proximate cause of the fire at the Provo Tabernacle on December 16, Finally, the drop down fire on the elevated stage observed by the security guard at approximately 0243 is secondary to a heat source, specifically an incandescent light fixture, with an energized 300-watt lamp, is supported as an extension of the cause of the fire at the Provo Tabernacle. 73

82 Fire Ignition and Spread Based on witness statement, evidence found in the excavation of the structure and testing, the Task Force has concluded that the most probable source of ignition was the southeast incandescent light fixture. This fixture was removed to suspend the lighting truss. According to witnesses Crane, Rasmussen, and Knecht, this fixture was armed (had a lamp in the receptacle) as of Tuesday evening December 14, In addition, the presence of lamps in the light fixtures was a point of emphasis in the facilities maintenance group. Jeremy Ostler indicated that he set the fixture aside to suspend the lighting truss. The photograph provided by Scott Morgan shows the southeast incandescent light fixture on the center wooden speaker enclosure. He does not present a consistent account of the status of the lamp or fixture. In fact, during the two interviews he gave contradictory accounts of the light fixture status. Mr. Ostler states that there were not lamps however, he does not indicate how that was determined, nor does he offer an affirmative statement that he looked for, or removed, the lamps from the fixtures. The southeast light fixture, according to the facilities maintenance group, was similar to the metal halide lights that ran parallel to length of the building. The reflective bell was polished on the interior similar to the fixture found in the excavation, and there was no lens in the decorative ring. According to Pete Crane, the south east incandescent light fixture had a Sylvania 300-watt lamp. He also stated that the northeast incandescent light fixtures lamp was burned out. The reflective bell found during the excavation, and identified by Mr. Knecht as part of the dimmable light system had thermal damage at the top of the reflective bell. This is indicative of high interior temperatures that resulted in icicle type formations inside of the bell and flowing formations on the exteriors. This leads us to conclude that this was the heat source that ignited the fire. The location of the fixture identified as the point of origin is shown in figure 66 and

83 Figure 66: Point of Origin Point of origin Dimmable incandescent lights 75

84 Figure 67: Point of Origin Interior View Incandescent light fixture set aside to suspend the lighting truss Most probable point of fire origin Photo courtesy of Tyler Weston The material first ignited was a wooden speaker enclosure. Based on testing, investigators have concluded that the ignition sequence included the wooden speaker enclosure. Based on testing, this event probably occurred approximately two and one-half hours after the six incandescent lights over the stage area were energized. It is probable that the ignition sequence for this fire was complete and the self-sustaining combustion was occurring, when Camera Operator Bunton said I smell smoke at The speaker enclosure would have been heated to its ignition temperature and, at a minimum, in a state of glowing combustion prior to the incandescent lights being turned off sometime between 2215 and 2300, December 16, Once a sufficient air supply was achieved, flaming combustion would most probably have accelerated the fire spread along the ceiling deck and in the interstitial space, burning down to the wooden lath. The fire spread vertically due to several available ladder fuels that carried the fire into the truss structure. Figure 68 shows the available ladder fuels as well as the orientation of the lighting truss suspension system. 76

85 Figure 68: Available Attic Fuel Load and Heat Sources Center of truss system 2 x 6 wooden steps to cross air handling duct Incandescent light fixture set aside to suspend lighting truss South triangular truss used to suspend the light truss Chain Motor Box North triangular truss used to suspend the light truss Wooden Speaker Enclosure Photo courtesy of Scott Morgan The fire spread continued up the wooden steps and into the truss structure as shown above. The fuel arrangement in the truss system was such that it would have supported slow flaming combustion. In the 1985 remodel, any gaps in the truss system were filled with an epoxy grout. That created a solid 20 x 12 inch truss, which would have taken several hours to weaken to the point of collapse. The fire would continue to grow in an inverted conical shape above the point of origin. In this incident the Task Force have concluded that the fire was controlled, to a point, by access to oxygen. The attic space of the Tabernacle was approximately 54,000 cubic feet; in addition it was not an air tight space. Air would have been free to move in through the two lights that were set aside to suspend the lighting truss and also the air handling ducts. Third, the fire is suppressed. In this incident, fire investigators have concluded that the fire was controlled to a point by access to oxygen. 77

86 Once the fire began to work its way through the attic space the consumption of oxygen began to out pace the oxygen flowing into the attic space. As the fire continued to grow on the southwest end the attic filled with smoke and heated gases causing heating of the attic and roof by convective and radiant heat. At 0100, W-13 Hopkins saw a light colored fog in the lights on the east side of the Tabernacle. It can be concluded that the attic space was completely full of smoke and hot gases and the smoke was venting to the outside at this time. The attic smoke detectors went into alarm some time prior to The smoke alarms in the attic space were located on the north portion of the attic approximately 10 feet off of the ceiling deck. This is well below the crest of the roof. It can be concluded from the alarm system design that approximately one third of the attic space would have to be charged with smoke to activate the alarm system. In addition, the system failed inspection on December 2, 2010 due to detector sensitivity. It can be reasonably concluded that the fire was well established within the structure before the detectors went into alarm. The advanced stage of the fire is also demonstrated by W-1 Williams who described crackling and popping sounds in the ceiling when he was on the northeast balcony looking for intruders. The fire continued to consume the truss system on the west side of the building. The fire became ventilation-controlled when the free burning fire required more oxygen than was available. At some point before 0243 the ceiling collapsed in the area identified by W-1 Williams. The collapse enabled more air into the attic space, forcing smoke out of the structure and returning the fire to a free burning state. Figure 69 shows the smoke patterns that presented to the first arriving fire units. 78

87 Figure 69: Initial Smoke Conditions Gray smoke coming from west soffit and upper window Note the heavy black smoke coming out of the gable and soffit Photo courtesy of A.Williams As illustrated in Figure 69, the dark black smoke coming from the east, west (not shown in this photograph) and south gable is indicative of incomplete combustion caused by an insufficient oxygen supply to the fire. The fire followed the oxygen supply by pushing down into the assembly area of the building. Figure 70 shows the fire behavior prior to the fire breaching the roof. 79

88 Figure 70: Visible Flames Pushing Out of the Ceiling Note the flame pushing down from the ceiling above the fire streams Photo courtesy of Tree Gore The fire breached the roof deck at approximately At approximately 0446 the west section of roof collapsed. The failure occurred at the trusses shown in Figure

89 Figure 71: Location of First Roof Collapse Area of fire origin Point of fire origin Area of first roof collapse at 0445 When the first section of the roof collapse occurred, the fire entered into a free burning state throughout the rest of the ceiling and roof deck until they were completely consumed. The fire continued to burn along the truss structure until approximately 0600, when the truss structure would not support itself any longer or the 6 x 6 angle iron was heated to the point that it twisted or buckled and caused the remainder of the truss structure to collapse, pulling in the gables over the north, south, and east entrances into the structure. When the roof structure collapsed into the structure, the fire continued to consume the interior of the building. The balcony continued to burn and subsequently collapsed to the floor, as did the truss structure and ceiling structure. The debris burned through the day and into the night. 81

90 Conclusions The Task Force has reached the following conclusions. Area of Origin The fire originated in the attic space in the area around the six dimmable incandescent lights. Point of Origin The point of origin was the wood enclosed speaker box located between the two eastern incandescent lights that were removed to suspend the lighting truss. The point of origin is shown in Figures 72 and 73. Figure 72: Interior View of the Point of Origin Speaker Enclosure The point of origin is the top of this enclosure Photo courtesy of Tyler Weston 82

91 Figure 73: The Point of Origin Heat of ignition. Energized 300 Watt Incandescent Lamp Most probable point of ignition Material first ignited sawn wood the speaker box enclosure Photo courtesy of Scott Morgan Cause The cause of this fire was accidental. Proximate Cause The proximate cause of this fire was a heat source, specifically the southeast incandescent light fixture with an energized 300-watt lamp that was placed too close to combustible materials, specifically the wooden speaker enclosure. Circumstances The Task Force has concluded that several independent intervening circumstances contributed to the ignition, growth, and scope of this fire. They include: Fire Protection Systems Fire Alarm The Tabernacle was equipped with a fire detection system that was designed and installed in The alarm system was tested on December 2, 2010 by Building Electronics System Technology LLC (BEST) and failed, due to smoke detector sensitivity. The 83