Upholstered Furniture Main Task Group Conference Call Meeting Agenda March 18, 2016

Transcription

1 Upholstered Furniture Main Task Group Conference Call Meeting Agenda March 18, Call to Order by Chair G. Damant 2. Introductions 3. Review draft summary of task group activities from R. Gann (attached PDF) 4. Review 277 draft comments from G. Damant (attached PDF) 5. Review 277 draft test method (modified NFPA 266) (attached PDF) 6. Prepare Task Group Report 7. Next Meeting 8. Adjournment

2 Appendix A Commentary Draft Appendix for NFPA 277 RGG; 3/11/2016 This appendix is not part of the requirements of this NFPA document, but is included for informational purposes only. A.1 Purpose. NFPA 277 was commissioned to fill the void created when the State of California removed the flaming ignition test from its Technical Bulletin 117 (TB 117). 1 This modification was done in the midst of claims (a) that meeting the TB 117 small flame resistance requirement required the use of flame retardant additives, (b) that flame retardants posed threats to people and the environment, and (c) that the small flame test had not increased fire safety. A.2 Fire Scenario. A.2.1 The role of residential upholstered furniture (RUF) as the first item ignited The fire threat addressed by the flame test in TB 117 was that of a match, candle, or other small flame being applied to the seating area of a chair or sofa. 2 U.S. fire incidence statistics indicated that there were approximately 1450 fires annually resulting from a RUF item being ignited by a small flame. These fires resulted in annual averages of 70 deaths, 230 reported injuries, and $75 million in direct property loss, all from 2005 through A.2.2 The role of residential upholstered furniture (RUF) as a subsequent ignited item Two workshops significantly altered the focus of the role of RUF in fire losses. In December 2012, the U.S. Fire Administration hosted a workshop entitled Changing Severity of Home Fires. 4 A common factor in some presentations was that over the past few decades, fires were growing faster than they used to. This increased growth rate was attributed to changes in the materials in common combustibles and the increased mass loading of combustible items in households. There are few household combustibles whose burning accelerates quickly and whose burning rate is high enough and sufficiently sustained to account for the observed high growth rates in actual fires. Soft furnishings, i.e. upholstered furniture and beds, are the most prevalent items. However, since July 1, 2007, the peak heat release rate of new mattresses and mattress sets has been limited to 200 kw during the first 30 minutes following ignition by a burner simulating the fire from burning bedclothes. 5 The regulation also limits the total heat output of the mattress set to15 kj during the first 10 minutes of the test. While the mass and extent of carpeting in a residential room might appear to fit in this category, it must meet ignition 6 and flame spread 7 criteria. Thus, carpeting is generally not a major cause of rapid fire growth until the room is already engulfed in flames. Curtains and draperies might burn intensely, but do not sustain a high burning rate long enough to ignite hard furnishings or interior finish. 8 This leaves RUF items as the most prominent of the household combustibles capable of rapidly amplifying the hazard from a small fire. The European CBUF project 9 had shown that upholstered furniture of different compositions could have markedly different peak rates of heat release and reach those peaks at different times. More recently, this was visualized by a film clip from Underwriters Laboratories that compared the burning of a piece of legacy RUF with the 1

3 burning of a piece of modern RUF. 10 The former chair reached a peak heat release rate of xxx kw at about xx minutes. By contrast, the modern chair reached a peak of xx kw in xx minutes. In March 2012, the National Institute of Standards and Technology (NIST) hosted a workshop entitled Quantifying the Contribution of Flaming Residential Upholstered Furniture to Fire Losses in the United States. 11 There, a circumstantial case was made for a significant contribution to fire losses of RUF items that were ignited by previously ignited combustibles. Following that workshop, John Hall of NFPA analyzed data from the U.S. National Fire Incident Reporting System. His estimates were that this additional set of fire scenarios led to 2200 fires, 130 fire deaths, 280 reported injuries, and $140 million in direct property loss annually between 2006 and Using a different analytical technique, Butry and Thomas found similar results: 4600 fires, 130 fire deaths, 350 reported injuries, and $175 million in direct property loss annually. 13 The difference between these two sets of estimates is within the uncertainty in the database and the analytical methods. Of most importance, the deaths and property losses from the second item ignited scenario are significantly larger than the losses from fires in which the RUF item is the first item ignited by a small open flame. A.2.3 Ignition of RUF by an already burning item Marty Ahrens of NFPA provided NFPA s compilation of the types of first burning items that might be igniting the RUF items in injurious and fatal fires (Table 1). 14 Table 1. Item First Ignited in Home Structure Fires in which Upholstered Furniture Contributed to Flame Spread beyond the Object of Origin: Annual Averages. Fires Civilian Deaths Civilian Injuries Direct Property Damage ($ millions) Item First ignited No. % No. % No. % No. % Unclassified furniture or utensil $18 13 Electrical wire or cable insulation $11 8 Mattress, pillow, blanket or other bedding $17 12 Floor covering $8 6 Unclassified item first ignited $6 4 Magazine, newspaper, or writing paper $8 6 Multiple items first ignited $4 3 Clothing $7 5 Interior wall covering $5 3 Rubbish, trash, or waste $5 3 Flammable or combustible liquid or gas, piping, or filter $8 6 Structural member or framing $9 6 Curtain, blind, drapery, or tapestry $4 3 Unclassified soft goods or wearing apparel $4 3 Appliance housing or casing $4 3 2

4 Cabinetry $4 3 Box, carton, bag, basket, or barrel $2 1 Other items (each 1 % of total) $18 12 Total These items would expose a RUF item to flames which burn longer and more intensely, and which expose a larger area of the RUF surface, than the small burners in flaming ignition resistance tests. Moreover, the flames from the first burning item do not necessarily impinge on the seating surface of the RUF item. This led the Task Group of the NFPA Committee on Fire Tests to develop a table of estimates of the ignition threat faced by a RUF item (Table 2). 15 The ignition burner previously used in the California TB 117 flame resistance test is also included for comparison. Table 2. Scenarios for Flaming Ignition of Residential Upholstered Furniture No. Surface Exposed Components Exposed Ignition Source and Nature Source Expanse Intensity Duration 1 Hem, dust cover Fabric Match Few mm 1 kw Few s Top of seat cushion, arms, crevice, back 2 Top of seat cushion, crevice, top of arms, back 3 Seat cushion, underside, arms, back 4 Seat cushion and surrounding crevices 5 Top of back, tops of arms, tops of seat cushions 6 Exterior of back and sides 7 Interior surfaces of seat, arms, and back 8 External surface: back or sides External surface: back or sides Fabric over (multiple) paddings Fabric over (multiple) paddings Fabric over (multiple) paddings Fabric, seat and surrounding paddings Fabric over (multiple) paddings Exterior fabric over undersupport Fabric over (multiple) paddings Exterior fabric over undersupport Exterior fabric over undersupport Match Few mm 1 kw Few s Candle Few cm 1 kw Several min Lit fluid (e.g., accelerant) Transition from RUF smoldering to flaming Curtains 9 Underside Fabric Electrical extension cords 10 Back Fabric, undersupport Electrical - outlets 11 Interior surfaces of seat, arms, and back Fabric over (multiple) paddings 10s of cm 10s of kw Few min 10s of cm 10s of kw 1 s 10s of cm to 1 m 10s to 100s of kw Space heater 10s of cm 10 to 20 kw/m 2 Trash on RUF 10s of cm 10 to 20 kw/m 2 1 min Hours Several min External trash 10s of cm 10s of kw Several min Trash basket 10s of cm 50+ kw Several min Decorative pillow Few cm Arc? Few s Few cm Arc? Few s 10s of cm 100s of kw Several min TB 117 flame 1 cm 1 kw? 12 s 3

5 A.3 Test function There are two approaches to increasing the fire safety of a product. Reduce the probability that the item will become ignited, i.e., increase its ignition resistance. Limit the consequences of the item once it is ignited, e.g., limit the heat release rate. The NFPA Task Group identified multiple reasons to pursue the second approach for a complex product like an upholstered chair. With sections of the chair having different components, and the variety of ignition locations as shown in Table 2, it was not clear how to construct the test specimen for ignition resistance. Ignitions in different locations could have significantly different impacts on the resulting fire losses. It would be necessary to conduct multiple tests for each RUF item or to be able to determine the location where an ignition would have the worst consequences. The ignition sources in Table 2 are sufficiently strong that providing reliable ignition resistance would be difficult. The consequences of a RUF item not resisting a particular ignition source are not necessarily severe. By contrast, focusing on limiting the post-ignition heat release rate (HRR) can directly decrease the likelihood of an undesirable consequence, such as the room reaching flashover. The HRR of a burning item has long been recognized as the most important metric for fire hazard. 8 Since much of the fire loss from smoldering ignition is realized after the smoldering transitions to flaming, the consequences of those fires might be limited as well. For these reasons, the Task Force focused on a test that would measure the timing, intensity, and duration of the HRR, rather than on a test to measure ignition resistance. A.4 Design of the method of test A.4.1 Test scale Based on the above considerations, the NFPA Task Group recognized that the initial need was for a full-scale reference test for the response of a RUF item to a substantial flaming ignition source. The test results could be used to verify that the knowledge or assumptions used to design a RUF item did indeed result in furniture of low HRR. In addition, the test results could be used to determine compliance with any regulations regarding RUF burning performance. The Task Group also recognized that this test could not be used to provide guidance to manufacturers in designing and producing furniture of reduced HRR to meet a customer order. The RUF HRR integrates such factors as the fire and thermal properties of the component materials, the interactions among those materials as they burn, the initial geometry of the RUF item, and the changes in that geometry as the burning proceeds. In the marketplace at any given time are thousands of upholstery fabrics, tens of padding materials, a variety of interliner materials, and hundreds of RUF designs. The fabrics and designs are a matter of fashion and therefore change frequently. It is not practical to manufacture a RUF item and perform (a series 4

6 of replicate) full-scale fire tests before informing the customer whether their item meets a flammability requirement. This kind of guidance would need to come from one or more small-scale tests, ideally of RUF components. This is the territory of a further testing methodology. A.4.2 Estimated range of HRR values to be measured The anticipated range of peak HRR values that would significantly reduce fire losses is a key factor in determining the apparatus and procedure for conducting the full-scale test of a RUF item. From the NFPA fire incidence analysis, containing the fire in the room of origin (equivalent to preventing room flashover) is an objective whose frequency is measurable. As an incipient RUF fire grows, the temperature in the fire room and the toxic gas generation rate from the burning RUF item both rise, threatening people in the room. However, prior to flashover, the HRR is still sufficiently low that little heat and gas are flowing out of the room. The threat to people and property is mainly within the fire room. At the point of room flashover, the radiant heat is pyrolyzing fuel vapors from multiple combustibles in the fire room. Due to the high mass burning rate, the oxygen in the room has been depleted to a level that does not support combustion of all the fuel vapors. The heat buildup in the room increases the pressure and drives this hot, unburned fuel out room openings, where it encounters an ample supply of oxygen-containing fresh air, and the fuel vapor ignites. The fire, heat, and combustion products rapidly spread to adjacent spaces and possibly throughout the building. A larger number of people are threatened and the property damage increases. NFPA analysis indicates that approximately half of the fire victims were outside the fire room at the time of the fire incident. 16 The HRR that results in a room reaching flashover is determined primarily by the size of the room openings and secondarily by the volume of the room. A typical residential room can flash over when the HRR reaches approximately 1 MW. CHECK THIS FOR DIFFERENT FLOOR AREAS AND DOOR OPENINGS. Thus, if a burning RUF item generates a peak HRR of 1 MW, it alone will extend the fire hazard outside the fire room. A large fraction of RUF items generate peak HRR values well in excess of 1 MW. Generally, there are multiple pieces of RUF in a den or living room. If one RUF item were to ignite a second combustible, then the combined HRR could lead to room flashover, even if the burning of a single piece does not. Therefore, the 1 MW limit to the peak HRR of a single RUF item is an upper limit if room flashover is to be avoided. Ohlemiller and Gann developed a protocol for estimating the likelihood of a burning item igniting another burning item. 17 While directed at the case of a burning bed igniting a second object in a bedroom, the fire physics is broadly applicable, including to the scenario of interest here. Tests of three types of mattresses included measurements of the bed s HRR, lateral flame extension (from video recording), and radiant flux to eight locations. For a bed with a peak HRR of approximately 400 kw, the lateral flame reach was on the order of 20 cm. For a bed with approximately triple the peak HRR, the lateral flame reach was approximately 35 cm. Measurements of minimum radiant flux for (piloted and unpiloted) ignition were made using a cone calorimeter. 18 The test specimens were of materials typical of soft furnishings (i.e., upholstery fabrics) and hard furnishings (i.e., woods). The combination of radiant flux 5

7 measurements from the mattress tests and ignition tests from the cone calorimeter indicate that there is a good chance that a burning RUF item would ignite an RUF item if the separation were approximately 30 cm (one foot) or less. The peak HRR from the two burning RUF items would no more than the sum of the HRR peaks from the individual items. The combined peak might be lower if the second item does not reach its peak burning rate until the flaming from the first item has subsided. For the purpose of estimating the peak HRR value for an ensemble of RUF items, we assumed that the peak HRR values of the first two RUF items were additive (a somewhat conservative estimate) and that by the time that a third RUF item ignited, the first item had burned out. The CBUF data indicate a peak HRR repeatability of ± 20 % for an armchair and ± 30 % for a sofa. Combined, these findings suggest that a single RUF item with a peak HRR value of 400 kw and in the presence of similar RUF items, is at the threshold of posing a risk of initiating room flashover. A.4.3 Test configuration There are reasons for testing RUF items in a room rather than in an open calorimeter. For room-test HRR values above about 250 kw, thermal radiation from the heated walls and the accumulated hot gases in the upper layer of the room enhances the burning rate of the test specimen. When the same specimen is tested in an open calorimeter, this thermal enhancement is absent. Thus, it is possible to measure a lower peak HRR in an open calorimeter that would be experienced if the RUF item burned in a household setting. Flaming combustion is sensitive to ambient air drafts. These are readily controlled in a room test and less so in an open calorimeter. Thus, the test protocol for NFPA 277 specifies testing in a room. Laboratories that perform this type of testing generally have a test room that conforms to ISO , ASTM , and NFPA The dimensions are 2.44 m x 3.66 m x 2.44 m high. There is a doorway that is 0.76 m wide x 2.03 m high in the narrow wall. Placing the test article in the middle of the room minimizes the thermal feedback from the hot walls. The more conservative configuration is with the test article against the wall opposite the door. A.4.4 Ignition source The first consideration is site where the ignition burner is to be applied. For the materials currently used in RUF, the peak HRR is largely due to the burning of the seating area (i.e., the padding materials, with some contribution from the upholstery fabric). 22 This suggests applying the flame directly to the seating are, as is done in California Technical Bulletin Table 1 indicates that the actual ignition sites are in both the seating area and on the exterior of the RUF item. For exterior ignition, it is possible that the upholstery fabric could spread flames rapidly. This is likely to lead to a short HRR peak which is less a threat to a second RUF item than the eventual burning of the combination of seating materials. It is also possible that the ignition source burns through the upholstery fabric and its backing. This results in rapid contact between the flame and the seating materials. The Task Group recognized that applying the burner directly 6

8 to the seating area captures the essence of the multiple real-world ignition scenarios without the variability and expense of testing at different ignition sites. The second consideration is the burner design and operating conditions. The Task Group felt that the square burner used in TB 133, and applied for 80 s, was sufficient to capture the threat of the ignition conditions in Table 1 and Table 2 and was already in use. A.5 Measurements A.5.1 Heat release rate The heat generated by the burning RUF item determines the heating of the fire room and the potential for room flashover. Therefore, it is necessary to measure the heat release rate from the beginning of the test until the test specimen exceeds a prescribed upper HRR limit or until the test specimen is no longer flaming. If, by analogy with 16 CFR Part 1633 for mattress sets, the total heat release for a particular time interval is needed, this can be obtained by integrating the area under that part of the plot of heat release rate vs. time. A.5.2 Potential for ignition of a subsequent combustible The rationale for estimating the range of expected peak HRR values included possible ignition of a subsequent combustible. Thus, no additional measurement is essential. We could add a heat flux gauge at a prescribed location to ensure that the radiant flux from a RUF item of future materials doesn t pose an unexpected hazard. 1 California Technical Bulletin TB , Requirements, Test Procedure and Apparatus for Testing the Smolder Retardance of Resilient Filling Materials, Bureau of Appliance Repair, Home Furnishings and Thermal Insulation, Sacramento, CA, January California Technical Bulletin TB 117, Requirements, Test Procedure and Apparatus for Testing the Flame Retardance of Resilient Filling Materials, Bureau of Home Furnishings and Thermal Insulation, Sacramento, CA, March Ahrens, M., Home Fires that Began with Upholstered Furniture, National Fire Protection Association, August Changing Severity of Home Fires Workshop Report, U.S. Fire Administration, Emmitsburg, MD, CFR Part 1633, Standard for the Flammability (Open Flame) of Mattress Sets; Final Rule, (U.S.) Consumer Product Safety Commission, Federal Register, March 15, ASTM D2859, Standard Test Method for Ignition Characteristics of Finished Textile Floor Covering Materials, ASTM International, West Conshohocken, PA, NFPA 253, Standard Method of Test for Critical Radiant Flux of Floor Covering Systems Using a Radiant Heat Energy Source, National Fire Protection Association, Quincy, MA, Babrauskas, V., Heat Release Rates, Chapter 1, Section 3, SFPE Handbook of Fire Protection Engineering, 4 th edition, Society of Fire Protection Engineers, Gaithersburg, MD, Fire Safety of Upholstered Furniture The Final Report on the CBUF Research Programme, Interscience Communication Ltd., London, UK, UL film clip. UTUBE? 7

9 11 Pitts, W.M., Summary and Conclusions of a Workshop on Quantifying the Contribution of Flaming Residential Upholstered Furniture to Fire Losses in the United States, NIST Technical Note 1757r1, National Institute of Standards and Technology, Gaithersburg, MD, August Hall, Jr., J.R., Estimating Fires When a Product is the Primary Fuel But Not the First Fuel, With an Application to Upholstered Furniture, Fire Technology 51 (2), , (2015). 13 Thomas, D.S, and Butry, D.T., Identifying Residential Fires Involving Upholstered Furniture within the National Fire Incident Reporting System, submitted for publication, Ahrens, M., Item First Ignited in Home Structure Fires in which Upholstered Furniture Contributed to Flame Spread Beyond the Object of Origin, National Fire Protection Association, Quincy, MA, October Minutes, September 11, 2014 meeting of the Upholstered Furniture Main Task Group of the Fire Test Committee Task Group, National Fire Protection Association, Quincy, MA, Ahrens, M., Home Structure Fires, National Fire Protection Association, April Ohlemiller, T.J., and Gann, R.G., "Estimating Reduced Fire Risk Resulting from an Improved Mattress Flammability Standard," NIST Technical Note 1446, National Institute of Standards and Technology, Gaithersburg, MD, August ASTM E1354, Standard Test for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen Consumption Calorimeter, ASTM International, West Conshohocken, PA, ISO , Reaction to Fire tests Room Corner Test for Wall and Ceiling Lining Products Part 1: Test Method for a Small Room Configuration, ISO, Geneva, ASTM 1537, Standard Test Method for Fire Testing of Upholstered Furniture, ASTM International, West Conshohocken, PA, NFPA 286, Standard Methods of Tests for Evaluating Contribution of Wall and Ceiling Interior Finish to Room Fire Growth, National Fire Protection Association, Quincy, MA, October Pitts, W.M., in preparation. 23 California Technical Bulleting TB 133, Flammability Test Procedure for Seating Furniture for Use in Public Occupancies, Bureau of Home Furnishings and Thermal Insulation, Sacramento, CA, January,

10 NFPA 277 I have been able to review the NFPA prior version of NFPA 266. Some changes have been made to make the prior test method consistent with Task Group activities related to NFPA 277. The following are my comments regards decisions that the NFPA Task Group may still need to address. I think that the basic draft test method is in pretty good shape. The following is my assessment of some key issues that the task group may need to address in the new standard 277 test method. Future Task Group Activities related to NFPA 277, based upon a prior version of NFPA 266. Chapter 2 Referenced publications There is additional work that the task group needs to do in this section to make the information current. Chapter 9 Report of Results The task group needs to decide if NFPA 277 needs all of the test documentation previously required by NFPA 266. Also, I think that a critical requirement of TB 277 should be that all tests are videotaped. This does appear to be required by 266, but I have found that videotaping every test can provide very important test information, both the test personnel and furniture suppliers. Annex s The task group needs to review of all of the Annex material from NFPA 266 to determine what the task group wants to include in NFPA 277. Some of the Annex material from NFPA 266 may not be relevant to NFPA 277. Some of the current Annex material may need to be deleted and other material and information added. Here are some specific sections of the Annex material that the task group may need to review.

11 Annex A (Explanatory Material) Sections A through A The focus of Annex B ( Commentary) is currently on Institutional furniture. Since NFPA 277 will include residential furniture there may need to be a major modification to Annex B. The current version of Annex B provides extensive information and documentation about California TB 133, and an emphasis on the flammability of institutional furniture. The task group needs to decide if we want to make any changes to, or broaden the scope of NPFA 277 in this annex. Annex C (Heat Release Calculation Using Additional Gas Analysis) appears to generally acceptable. But we need to make sure that all of the information provided in Annex C is still current. Annex D (informational References). Similar to a review of Chapter 2 the task group needs to review Annex D to be sure that all of the currently reference publications are appropriate, and determine if other documents may need to be referenced. Additional comments about NFPA 277 The task group has had extensive discussions about pass/fail criteria for NFPA 277. Although NFPA standards do not typically provide pass/fail criteria, does the task group want to provide, either in the test method or an annex, some guidance to users of the document about the range of test results that can be expected using this test method, and of their significance? The test method, as currently written, allows the use of a large full scale furniture mock up to be tested. Does the task group wish to provide any

12 discussion or commentary, perhaps in an Annex, about the use of full scale furniture mock up testing. The task group has also had some discussion about a method of evaluating furniture components and composites. The task group needs to decide if this is a feasible approach to be included in a standard such as NFPA 277, or if it would be better for the furniture industry and their component suppliers to develop their own schemes/ methods to address this issue.

13 NFPA 277 Standard Method of Test for Upholstered Furniture Subject to a Flaming Ignition Source Chapter 1 General 1.1 Scope The test method shall apply to full-scale residential upholstered furniture The test method shall evaluate the peak heat release rate, the total heat release rate, and the maximum radiant flux Heat release rate is indicated by measurement of oxygen depletion, and smoke generation is determined by smoke density measurement systems. Weight loss and carbon monoxide (CO) and carbon dioxide (CO2) evolution are continuously recorded With respect to measurement of smoke and CO production, a quantitative relationship has not been established between measurements taken in the duct of the calorimeter exhaust system and measurements taken within the room. Accordingly, results of measurements of CO and smoke taken at different locations in different test environments shall not be considered equivalent. 1.2 Purpose The purpose of this standard is to provide a test to determine whether furniture will contribute to room flashover or ignition of additional items of residential upholstered furniture This test method shall be used to determine performance of residential upholstered furniture exposed to a flaming ignition source This test method shall be used to determine the resulting fire performance characteristics of upholstered furniture or full-scale mock-ups when exposed to a standard flaming ignition source The results from this procedure provide information that shall be permitted to be used as an aid in the selection of upholstered furniture items that provide less contribution of heat, flame, smoke, and gases to fire scenarios.

14 1.2.3 Heat and smoke release rate measurements are sources of useful information for product development. They provide a quantitative measure of specific changes in fire performance caused by product modifications * For upholstered furniture products containing only wood or a metal frame, or a combination of both, the procedure using a mock-up sample provides an indication of the openflame performance of the finished article. For upholstered furniture products containing plastic frames and plastic decorative parts or special construction features, a mock-up sample is not always an accurate indicator of the open-flame performance of the finished article. 1.3 Summary of Test Method This procedure shall provide for exposure of full-size upholstered furniture specimens or furniture mock-ups to a standard flaming ignition source in a full-scale furniture calorimeter The standard ignition source shall be a gas burner Determinations shall be made and recorded for parameters that include density of smoke, concentrations of carbon monoxide and carbon dioxide, weight loss, heat release rate, and total heat release. 1.4 Units Metric units of measurement in this standard are in accordance with the modernized metric system known as the International System of Units (SI) If a value for measurement as given in this standard is followed by an equivalent value in other units, the first stated shall be regarded as the requirement. A given equivalent value shall be considered as approximate.

15 Chapter 2 Referenced Publications 2.1 General. The documents or portions thereof listed in this chapter are referenced within this standard and shall be considered part of the requirements of this document. 2.2 NFPA Publications. National Fire Protection Association, 1 Batterymarch Park, Quincy, MA Other Publications Other Publications. Merriam-Webster s Collegiate Dictionary, 11 th edition, Merriam-Webster, Inc., Springfield, MA, References for Extracts in Mandatory Sections. Chapter 3 Definitions 3.1 General. The definitions contained in this chapter shall apply to the terms used in this standard. Where terms are not defined in this chapter or within another chapter, they shall be defined using their ordinarily accepted meanings within the context in which they are used. Merriam-Webster s Collegiate Dictionary, 11 th edition, shall be the source for the ordinarily accepted meaning. 3.2 NFPA Official Definitions Shall. Indicates a mandatory requirement Should. Indicates a recommendation or that which is advised but not required.

16 3.2.3 Standard. An NFPA Standard, the main text of which contains only mandatory provisions using the word shall to indicate requirements and that is in a form generally suitable for mandatory reference by another standard or code or for adoption into law. Nonmandatory provisions are not to be considered a part of the requirements of a standard and shall be located in an appendix, annex, footnote, informational note, or other means as permitted in the NFPA Manuals of Style. When used in a generic sense, such as in the phrase standards development process or standards development activities, the term standards includes all NFPA Standards, including Codes, Standards, Recommended Practices, and Guides. 3.3 General Definitions. Suggested entries (from NFPA 261): Furniture Mock-Up. A representation of production furniture that uses the same upholstery cover material and upholstery material, assembled in the same manner as in production furniture but with straight, vertical sides. Upholstered Furniture. For the purpose of this test method, a unit of interior furnishing that has any surface covered, in whole or in part, with a fabric or related upholstery cover material, contains upholstery material, and is intended or promoted for sitting or reclining. Chapter 4 Test Specimens 4.1 Size and Preparation * The test specimen shall consist of the actual upholstered furniture item or a full-scale mock-up of the furniture * The construction of any full-scale mock-up upholstered furniture shall simulate the actual construction of the upholstered item The test specimen for a full-scale mock-up shall consist of component cushions that duplicate the thickness, construction, and design features of the product.

17 4.1.4 In the case of mock-up testing, a metal test frame [see Figure 4.1.4(a) and Figure 4.1.4(b)] shall be used to support the seat and back cushions and, if necessary, arm cushions. The chair frame shall be constructed of slotted L-angle iron and slotted flat-angle iron. The back shall be constructed so that it is adjustable to a maximum angle of 135 degrees ± 2 degrees from the horizontal plane. The test frame shall be adjustable to accommodate test cushions of various thicknesses and sizes, with or without arm cushions. Figure 4.1.4(a) Metal Test Frame. Figure 4.1.4(b) Metal Test Frame (end view).

18 4.1.5 Component back, seat, and arm cushions shall be constructed into mock-up designs of the actual article of furniture. Construction shall duplicate all layers found in the actual article of furniture. Cushion construction shall consist of either a manufacturer s prefabricated cushion of the appropriate size or custom-made cushions. Custom-made cushions shall be constructed by covering all six faces of the filling material with the appropriate interliners and cover fabric In the case of mock-up testing, the constructed seat cushion shall be placed horizontally on the seat area of the test frame and pushed against the back of the frame. The constructed back cushion shall then be placed vertically against the back support of the test frame. The back cushion shall be held in place by wire to prevent it from falling forward If arm cushions are used, the constructed arm cushions shall be placed between the seat cushion and the arm supports of the test frame. However, the placement of the seat, back, and arm cushions shall simulate the design features of the completed article of furniture. 4.2 Conditioning. The test specimen shall be conditioned for at least 48 hours prior to testing at 23 C ± 3 C (73 F ± 5 F) and a relative humidity of 50 percent ± 5 percent. Test specimens shall be tested within 10 minutes of removal from such conditions if the test conditions differ from those specified in this section. Chapter 5 Test Equipment and Instrumentation 5.1 Ignition Source A 250 mm ± 10 mm 250 mm ± 10 mm (10 in. ± 0.39 in. 10 in. ± 0.39 in.) burner shall be used as the ignition source in this test method. The burner shall be constructed of 13 mm ± 1 mm (0.5 in. ± in.) outside diameter stainless steel tubing with 0.89 mm ± 0.05 mm (0.034 in. ± in.) wall thickness [see Figure 5.1.1(a)]. The front side shall have 14 holes pointing straight out and spaced 13 mm ± 1 mm (0.5 in. ± in.) apart. The right and left sides shall have 6 holes pointing straight out and spaced 13 mm ± 1 mm (0.5 in. ± in.) apart, and 4 holes pointing inward at an angle of 45 degrees ± 2 degrees and spaced 50 mm ± 2 mm (2 in. ± in.) apart. All holes shall be 1 mm ± 0.1 mm (0.039 in. ± in.) in diameter [see Figure 5.1.1(b)]. The 1.07 m ± 0.2 m (42 in. ± 7.9 in.) straight arm of the burner shall be welded

19 onto the rear of the front side [see Figure 5.1.1(c)] at a 30-degree angle. The burner shall be mounted on an adjustable height pole and shall be balanced by a counterweight or other appropriate mechanism. [See Figure 5.1.1(d).] Figure 5.1.1(a) Plan View of Square Gas Burner. Figure 5.1.1(b) Cross-Sectional View of Each Side of Square Gas Burner. Figure 5.1.1(c) Side View of Square Gas Burner.

20 Figure 5.1.1(d) Positioning of Square Gas Burner on the Chair The gas burner shall utilize commercial-grade propane gas as fuel. 5.2 Collection Exhaust System The hood shall be installed centrally above the weight-measuring system and test specimen. The face dimensions of the hood shall be 2.6 m ± 0.1 m 2.6 m ± 0.1 m (8.53 ft ± 0.32 ft 8.53 ft ± 0.32 ft), and the depth shall be 1.1 m ± 0.1 m (3.6 ft ± 0.32 ft). The hood shall exhaust into a plenum having a 0.9 m ± 0.05 m 0.9 m ± 0.05 m (2.9 ft ± 0.16 ft 2.9 ft ± 0.16 ft) cross section (see Figure 5.2.1). Other hood sizes shall be permitted, provided they produce equivalent test results. The distance between the lower edge of the hood and the weight-measuring system shall be 2.4 m (7.87 ft).

21 Figure Collection Hood and Exhaust Duct * The exhaust duct connected to the plenum shall be a minimum of 406 mm (15.8 in.) in diameter and shall have a minimum circular aperture of 305 mm (11.9 in.) at its entrance The exhaust system shall have sufficient exhaust capacity to collect all products of combustion developed by the burning specimen. The exhaust hood system shall be capable of being operated within a range that varies from a minimum rate of 0.47 m 3 /sec (16.6 ft 3 /sec) to a maximum rate of at least 2.4 m 3 /sec (84.8 ft 3 /sec) An alternate exhaust system design shall be permitted to be used if it has been shown to produce equivalent results. 5.3 Velocity Measuring Instruments The velocity in the exhaust duct shall be determined by measuring the differential pressure in the flow path using a bidirectional probe, as shown in Figure 5.3.1, connected to an electronic pressure gauge or an equivalent measuring system. The probe shall consist of a stainless steel cylinder with a solid diaphragm in the center that divides it into two chambers. The probe shall measure 44 mm (1.7 in.) long and have an inside diameter of 22 mm (0.86 in.). The pressure taps on either side of the diaphragm shall support the probe.

22 Figure Bidirectional Probe The axis of the probe shall be located at the centerline of the duct a minimum of 10 diameters downstream from the last turn in the duct. The taps shall be connected to a pressure transducer with a minimum resolution of 0.25 Pa (0.001 in. of water) The temperature of the exhaust gas shall be measured upstream 152 mm ± 15 mm (5.9 in. ± 0.6 in.) from the probe at the centerline of the duct with a No. 28 AWG (0.08 mm 2 ), Type K thermocouple with an inconel sheath having a 16 mm (0.62 in.) outside diameter and a thickness of 3 mm (0.12 in.). 5.4 Gas Sampling and Analysis Equipment * A stainless steel gas sampling tube shall be located at least 10 diameters downstream from the last turn in the duct to obtain a continuously flowing sample for determining the oxygen concentration of the exhaust gas as a function of time. A suitable filter and cold trap shall be placed in line ahead of the analyzer to remove particulates and water. The oxygen analyzer shall be of the paramagnetic type and shall be capable of measuring the oxygen concentration in a range of from 0 percent to 21 percent with an accuracy of ±0.2 percent of full-scale setting. The signal from the oxygen analyzer shall attain 90 percent of the calibration value within 30 seconds after introducing a step change in composition of the gas stream flowing past the inlet to the sampling tube * The gas sampling tube shall be located and defined as in The carbon monoxide analyzer shall be capable of measuring the carbon monoxide in a range of from 0 percent to 1.0 percent with an accuracy of ±0.02 percent of full-scale setting. The signal from the analyzer shall attain 90 percent of the calibration value within 30 seconds after introducing a step change in composition of the gas stream flowing past the inlet to the sampling tube.

23 5.4.3* The gas sampling tube shall be as located and described in The carbon dioxide analyzer shall be capable of measuring the carbon dioxide concentration in a range of from 0 percent to 10 percent with an accuracy of ±0.2 percent of full-scale setting. The signal from the analyzer shall attain 90 percent of the calibration value within 30 seconds after introducing a step change in composition of the gas stream flowing past the inlet to the sampling tube. 5.5 Smoke Density Measuring Instruments The smoke density measuring system shall be a white light system The lamp shall be of the incandescent filament type and shall operate at a color temperature of 2900 K ± 100 K. The lamp shall be supplied with stabilized direct current, stable within ±0.2 percent, including temperature and short-term and long-term stability The lens system shall be selected such that the lens shall have a diameter, d, chosen with regard to the focal length, f, so that d/f The aperture shall be placed in the focus of the lens The detector shall have a spectrally distributed response according to the CIE photopic curve. The detector shall be linear within 5 percent over an output range of at least 3.5 decades. This linearity shall be checked periodically with calibrated optical filters and shall cover the entire range of the instrument The system shall be mounted on a horizontal section of duct at a point where it will be preceded by a straight run of duct [at least 12 diameters or 5.2 m (17 ft)] and with the light beam directed upward along the vertical axis of the duct. A photoelectric cell, whose output is directly proportional to the amount of light received, shall be mounted over the light source and connected to a recording device. The recording device shall have an accuracy within ±1 percent of full scale for indicating changes in the attenuation of incident light resulting from the passage of smoke, particulate, and other effluents. The distance between the light source lens and the photocell lens shall be 914 mm ± 102 mm (35.6 in. ± 3.9 in.). The cylindrical light beam shall pass through 76 mm ± 3 mm (2.9 in. ± 0.12 in.) diameter openings at the top and bottom of the duct, with the resultant light beam centered on the photocell * An alternate smoke density measuring system shall be permitted to be used if it has been shown to produce equivalent results. 5.6 Weighing Platform Mass loss rate of the burning specimen shall be measured during the test by means of a weight-measuring device.

24 5.6.2 A weighing platform shall be used to support the test specimen during the test. A reinforced inorganic board having the dimensions 1.2 m ± 0.1 m 2.4 m ± 0.1 m (3.9 ft ± 0.32 ft 7.87 ft ± 0.32 ft) shall be located on top of the weighing platform. The weighing platform perimeter shall have a rim extending 0.1 m ± 10 mm (0.32 ft ± 0.38 ft) above the top surface of the inorganic board to prevent spillage of test material The weight-measuring device shall be capable of measuring a specimen mass up to at least 90 kg (198.5 lb) with an accuracy of at least ±150 g (±0.33 lb). It shall be installed in such a way that the heat from the burning specimen and any eccentricity of the load do not affect the accuracy. Care shall be taken to avoid range shifts during measurements. All parts of the weightmeasuring device shall be located below the top level of the slab The weighing platform shall support the base of the furniture specimen at a height of 127 mm ± 76 mm (5 in. ± 3 in.) above the floor The weighing platform shall be located beneath the collection hood at its geometric center. 5.7 Data Acquisition. A digital data acquisition system shall be used to collect and record oxygen, carbon monoxide, and carbon dioxide analyzer measurements; pressure gauge measurements; temperatures; smoke measurements; and weight measuring device measurements. The speed and capacity of the data system shall be sufficient to collect the data every 5 seconds. 5.8 Photographic and Video Equipment A camera and video equipment shall be used to record the test specimen performance throughout each test A pretest photographic record of the test specimen shall be made. Chapter 6 Calibration 6.1 Calibration of Equipment The equipment and instrumentation shall be calibrated The heat release instrumentation shall be calibrated by burning propane. A gas burner shall be constructed with a 100 mm ± 6 mm (3.9 in. ± 0.23 in.) layer of Ottawa sand to provide the horizontal surface through which the gas is supplied. This type of burner is shown in Figure The gas supply to the burner shall be of commercial grade propane and shall have a net heat of combustion of 46.4 MJ/kg ± 0.5 MJ/kg (20,000 Btu/lb ± 200 Btu/lb). The flow rate of propane shall be metered and kept constant throughout the calibration test. A heat release value of 160 kw shall be used for calibration. The test shall be conducted for a period of 10 minutes.

25 Figure Calibration Gas Burner.

26 6.1.3 A calibration constant, C, shall be obtained as described in Chapter 8. A value for C differing more than 10 percent from the theoretical value shall not be permitted, and the equipment shall be checked. For the exhaust duct configuration described in Section 5.2 and the velocity probe described in Section 5.3, C shall have a theoretical value of Daily Calibration Prior to the start of each day of testing, the equipment calibrations described in through shall be performed The oxygen analyzer shall be zeroed and spanned. The analyzer shall be zeroed by introducing 100 percent nitrogen gas to the instrument at the same pressure and flow rate as set for the test specimen combustion gases. The analyzer shall be spanned by introducing ambient duct air via the sample probe and adjusting the span to percent oxygen. The spanning and zeroing process shall continue until adjustment-free accuracy is obtained Following zeroing and spanning, linearity of the oxygen analyzer response curve shall be verified by introducing bottled gas of a known oxygen concentration to the analyzer. The delay time of the analyzer shall be checked by introducing ambient duct air to the analyzer and noting the time at which the analyzer readings reach 90 percent of the final reading The CO analyzer and CO2 analyzer shall be zeroed and spanned in the same manner as the oxygen analyzer. The analyzer shall be zeroed by introducing 100 percent nitrogen gas to the instrument at the same pressure and flow rate as set for the test specimen combustion gases. The analyzer shall be spanned by feeding each analyzer with bottled gas containing the selected concentration of span gas and adjusting for the response range of each analyzer The delay time of each analyzer shall be determined. The delay time shall be measured by introducing either a calibration span gas (for CO and CO2) or a zero gas (for O2) at the sample line just outside the duct and noting the time at which the analyzer readings reach 90 percent of the final reading The weight-measuring device shall be calibrated with known weights suitable for the capacity of the equipment and the specimen being tested Linearity of the smoke density measuring system shall be verified by interrupting the light beam with multiple calibrated neutral density filters to cover the range of the recording instrument. Transmittance values measured by the photometer, using neutral density filters, shall be within ±3 percent of the calibrated value for each filter.

27 Chapter 7 Test Procedure 7.1 Testing Procedure The test specimen and weighing platform shall be located as shown in Figure The initial exhaust hood flow rate shall be set at a minimum of 0.47 m 3 /sec (16.6 ft 3 /sec) The burner shall be positioned 51 mm ± 3 mm (2 in. ± 0.12 in.) from the back and 25 mm ± 3 mm (0.97 in. ± 0.12 in.) above the seat, with the center of the burner at the centerline of the test specimen The data acquisition shall begin in order to monitor test instrumentation The gas flow rate to the burner shall be set at a volume flow rate of 13 L/min ± 0.5 L/min (3.4 gal/min ± 0.13 gal/min). Care shall be taken to allow free flow of propane through the burner holes. Periodic cleaning of soot deposits and blowing of pressurized air through the tube shall be required The burner shall be ignited The exhaust hood flow rate shall be increased as required to collect all products of combustion from the test specimen The burner shall be removed from the test specimen after an exposure of 80 seconds ± 2 seconds The burner shall be turned off Combustion shall be allowed to continue until one or more of the following conditions are reached: (1) All flaming combustion has ceased. (2) Thirty minutes have elapsed from the time the burner was ignited.

28 Chapter 8 Calculations 8.1 Method of Calculation. The symbols used in this chapter shall be defined as in Section 8.2 and Annex C. The equations in this chapter shall assume that only oxygen is measured. Appropriate equations that shall be used for those cases where additional gas analysis equipment (CO2, CO, water vapor) is used are provided in Annex C. If a CO2 analyzer is used and CO2 is not removed from the oxygen sampling lines, then the appropriate equations in Annex C shall be used. 8.2 Symbols. The following symbols are used in this chapter: C = calibration constant using propane (m 1 / 2 kg 1 / 2 K 1/2 ) H c /r o = net heat released per kg of O2 consumed (kj/kg), where Hc equals net heat of combustion (kj/kg) and r0 equals stoichiometric oxygen/fuel mass ratio I I0 = light intensity = light intensity with no smoke k = extinction coefficient (m 1 ) L P = path length (m) = orifice meter pressure differential (Pa) q" = heat release rate per unit area (kw/m 2 ) t = time (sec) td Te = oxygen analyzer delay time (sec) = absolute temperature of gas at the orifice meter (K) X O2 = oxygen analyzer reading, mole fraction O2 0 X O2 = initial value of oxygen analyzer reading 1 X O2 = oxygen analyzer reading, before delay time correction