A.U.C. 180 March 15, 1997 PROCEDURES FOR FIRES AND EMERGENCIES IN MANHOLES AND/OR RELATED INSTALLATIONS 1. GENERAL

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1 A.U.C. 180 PROCEDURES FOR FIRES AND EMERGENCIES IN MANHOLES AND/OR RELATED INSTALLATIONS 1. GENERAL 1.1 The Officer in Command at the scene shall determine the cause and severity of the fire or emergency. Using signal 10-25, this officer shall transmit particulars to the dispatcher for immediate notification to the utility company concerned: Manhole or Transformer Fire or Emergency Any type of manhole or transformer fire or emergency. Without Code: Situation other than as described in Codes 1, 2, 3, or 4. Code 1: Code 2: Code 3: Code 4: Note: Fire has extended from a manhole, conduit, or transformer into a building. Fire has blown one or more manhole covers, or smoke is issuing from a manhole under pressure. Smoke is seeping from a manhole. Fire or smoke condition from a transformer at any location, i.e., pole, vault, room, etc. Utility Company will dispatch an emergency crew immediately upon receipt of a Code 1 or Code 4 signal. 1.2 Should conditions change after original report, a supplementary report shall be transmitted immediately to describe the existing conditions in accordance with the above code. 1.3 Utility company will dispatch an emergency crew immediately upon receipt of a Code 1 or Code 4 signal. If all crews are engaged, utility company will detach a crew operating at other than a Code 1 or Code 4 signal and direct such crew to respond immediately. 1.4 Units should be alert to the possibility that a manhole/transformer incident could have damaged the adjacent gas piping. If an odor of natural gas is encountered at these incidents, the dispatcher must be notified to request the immediate response of a utility's gas crew in addition to their electric crew. Additionally, downed overhead primary and secondary wires have the potential to damage underground gas piping. All gas piping (plastic, steel, cast iron and copper) can be impacted by burning, arching or smoldering electric cables. 2. OPERATIONAL GUIDELINES 2.1 The area shall be cordoned off to vehicular and pedestrian traffic. All apparatus shall be clear of the area in a safe location. Area shall be taped off. This marks the danger area for civilians and FD personnel. 1

2 2.2 Inspect electrical services in surrounding buildings. Units should use carbon monoxide meters when performing these inspections. Possible extension. This may also be the cause of the problem. 2.3 Members shall not attempt to move vehicles located in the danger area. 2.4 Precautionary hoselines shall be stretched as necessary. Units should not operate into manholes unless requested by a Con Edison employee at the scene. If requested to place water into a manhole, do not direct the stream directly into the manhole. Instead, let water flow or pour into the manhole. Use a fog nozzle to reduce or prevent any shock hazard. 2.5 The Officer in Charge shall order response of a utility company emergency crew and shall request the expected time of arrival. 2.6 When operations are within the capability of a single unit, the Officer in Command may leave one unit (preferably an Engine Company) to await the arrival of the emergency crew. If the expected time of arrival is more than 30 minutes, the Officer in Charge, based on evaluation of existing conditions, may order one of the following: A. The unit remaining on the scene may respond to assigned alarms received via department radio; one member shall be left at the scene. B. One member shall be left at the scene and the unit shall return to quarters. Company officers shall provide relief for members. C. When a member is left at the scene, the company officer shall at frequent intervals contact the dispatcher for re-notification of the utility company. D. The manhole shall be protected by traffic cones and tape, and all units placed in service. 2.7 During periods of multiple incidents within an area, the following actions may be authorized by the deputy chief in charge: One or more units shall be relieved from response assignments and utilized as follows: A. A member of the unit shall be left at the scene of each incident. B. The officer and the chauffeur shall remain with the apparatus to perform surveillance of the incident locations. C. Battalion chiefs shall provide for necessary relief of units or members. D. Deputy Chiefs may authorize the use of messenger vans and spare cars for travel and shelter of members at incident locations. 2.8 Members left at the scene of an incident shall: A. Be alert to changing conditions and shall call for assistance when necessary. B. Maintain surveillance of surrounding properties. C. Prevent entry to area by pedestrian or vehicular traffic. D. Obtain information necessary for required reports, under the direction of the immediate superior officer. 2 Rev. 10/04/11

3 2.9 Officers in Command shall request adequate Police Department response, depending upon the scope and severity of the fire or emergency. Such assistance shall be utilized where deemed necessary and with particular reference to sections 2.1, 2.3, 2.6.B, 2.6.D, 2.7.A, 2.8.C and Note #5 of this circular. NOTES: 1. Members are reminded that explosions in manholes are not uncommon and that they have caused serious burns to members of this department. 2. Members should not pull covers off electrical manholes at manhole fires or if a manhole fire is in the area. It is the responsibility of utility crews to open manhole covers at these incidents. Pulling covers may cause an explosion by mixing air with the gaseous products of combustion in the presence of an ignition source e.g., manhole fire and/or electric arcing. Note: This does not change Department policy of pulling electric manhole covers under certain circumstances at gas emergencies. (See Training Bulletin Emergencies 2). Be cautious of the PELLET EFFECT from the dirt and gravel that is trapped on the sides of the cover if an explosion occurs. 3. Explosions can take place after considerable time has elapsed and when the conditions in the manhole appear dormant. When a cover blows, do not run. Keep your eyes on the cover so you can approximate where it will land. 4. Serious explosions have also occurred in adjacent manholes that are connected by conduits with the originally involved manhole. 5. When operating at manhole emergencies, the location of traffic control boxes must be taken into consideration when deciding the size and location of the "AREA OF DANGER". The smoke and gases from a manhole incident can travel up the hollow pole of a nearby light stanchion and at times accumulate with considerable pressure. The gaseous mixture may be ignited by a spark inside the control box. 6. Hose lines stretched in the street to prevent involvement of adjacent properties should be positioned at a point beyond the predictable limits of fire or explosion damage. 7. Close and continuous supervision is required to keep citizens and Fire Department personnel at a safe distance and avoid injuries. 8. Where conditions indicate the electric lines in a building are becoming hot, hose lines shall be stretched and a thorough examination made. 9. Fire Department representation at the scene shall continue until all dangerous conditions are alleviated, or until informed by utility company emergency crew at scene that Fire Department presence is no longer required. Information for the required reports shall be obtained from the utility company personnel at the scene. 3 Rev. 04/19/11

4 3. TRANSFORMER VAULTS Members of this Department must recognize that underground transformer vaults present a highly volatile situation when encountered. All members must exercise extreme caution when these incidents occur. The use of full Personal Protection Clothing and SCBA, even in light smoke conditions, should be stressed when operating. 3.1 A word about sub-surface transformer vaults: A. CON EDISON distributes electricity throughout New York City by means of both overhead and underground power lines. Overhead transformers are easily recognizable since they are bolted to the tops of poles in the many residential areas throughout the city except in the Borough of Manhattan (See REFERENCE # 2). Underground transformers are not easily noticed since they are located in subsurface concrete structures. CON EDISON has stated that there are approximately 75,800 transformers citywide. The subsurface structures, known as transformer vaults, come in various sizes but a typical vault is approximately 12' x 4'. These vaults are installed either in the street or the sidewalk below grade level. B. To prevent subsurface transformers from overheating, slotted gratings are usually installed over the vaults to allow air to circulate and cool the transformer. Vaults in the street sometimes have solid gratings since heavy vehicles may cause damage to the weaker slotted gratings. The gratings are usually rectangular in shape. C. The transformers convert primary voltage (27,000 Volts) to secondary voltage (120 Volts) for use by CON EDISON customers. Either of these voltages can cause fatal injury if not handled properly. Some vaults contain submersible equipment, meaning that they function properly even if the vault is filled with water. Other vaults contain non-submersible equipment and must have a sump pump installed to prevent flooding. D. All transformers that are in the vaults contain dielectric oil, which acts as a coolant, in amounts ranging from 200 gallons to 600 gallons. The trade name for the newer oil that CON EDISON is presently using is SUN-OIL or MOBIL-X. This oil contains PCBs in the range of PPM and therefore is considered a Non-PCB Transformer. However, CON EDISON still has in use vault transformers that are considered PCB-CONTAMINATED TRANSFORMERS that contain PPM of PCBs. Note: The New York City Fire Department considers a transformer with any amount of PCBs as a PCB Transformer. Operate accordingly. 3.2 Hazard potential: A. Transformer Vaults can present many hazards to civilians and fire personnel. B. Environmental and physical dangers presented by transformer vaults include the presence of carbon monoxide or other gases in high concentrations, PVC in wire insulation, PCBs in transformers, high vapor pressures and the possibility of explosions. 4 Rev. 04/19/11

5 C. The possibility of asbestos may also be present, although the Environmental Protection Agency has mandated that any asbestos present must be removed in electrical vault systems. D. The greatest hazard of course is the amount of electricity that is contained in these vaults. 3.3 Safety precautions for operations: A. Units are to operate in accordance with guidelines as set forth in sections 1 & 2 of this bulletin & A.U.C. 266 PCBs Incidents B. Added emphasis shall be placed on the following: Cordon off and secure an area a safe distance from the vault for members and apparatus. It is not necessary for members to closely examine these vaults. Remember the potential dangers involved and the likelihood of an explosion that exists. There is inherent danger for serious injury, if the latter occurs. (See REFERENCE # 1) Full use of Personal Protective Clothing (PPC) and SCBA shall be adhered to. This type of incident can escalate very easily and unexpectedly. Be prepared to protect yourself. Stretch a precautionary handline. Due to the amount of flammable liquid contained in these transformers, Engine Companies shall also be prepared to initiate a foam operation if the need arises. Examination of surrounding exposures for extension of fire and/or gases through electrical conduits which service electricity to buildings. The main service panel is usually located in the cellar or basement. Units instructed to initiate this examination shall be guided by the following: 1) Teams of two members shall be used to examine an exposure. Each member shall be fully equipped with PPC, SCBA and Handi- Talkie. In addition, they shall carry a Carbon Monoxide Monitor. Readings shall be taken in the Meter Room, surrounding rooms, and on first floor, if necessary. High levels of CO have been found in exposures at these incidents. 2) Due to nature of these incidents and possible duration, it will be necessary to re-examine these exposures on a periodic basis. C. Monitor the situation and await arrival of Con Edison. 3.4 Remember the primary consideration at these types of incidents is the safety of civilians and fire personnel. BY ORDER OF THE FIRE COMMISSIONER AND CHIEF OF DEPARTMENT 5 Rev. 04/19/11

6 REFERENCE # 1 (FORMERLY SAFETY MESSAGE # 88) 1. INTRODUCTION The following narrative is an excerpt from a report on an unusual fire incident involving a Con Ed transformer vault. On Arrival Units Found A Light Smoke Condition Issuing From A Sidewalk Transformer Vault Adjacent To A 40 Story High Rise Office Building. Conditions At The Vault Deteriorated Rapidly With A Heavy Smoke Condition And Two Explosions Emanating From The Vault. After The Explosions, Conditions Some What Subsided And A Smoldering Fire Resulted Until Con Edison Cut The Power. Electricity To The High Rise Office Building Was Cut And An Examination Revealed No Extension. Units Stood By While Con Ed Made An Examination Of The Vault. Con Ed Found That The Cause Of The Fire Was The Theft Of Copper Bus Bars In The Vault. The Fire Involving The Vault Was Routine. The Cause Of The Fire Is Unusual In That Someone Entered This Vault And Remove Con Edison Equipment With The Power Still On. A Con Edison Official At The Scene Stated That The Theft Of These Copper Bus Bars Has Taken Place In The Past. 2. CONSIDERATIONS 2.1 Units arriving at the above incidents should be aware that there is a possibility that the perpetrator of these crimes has been trapped and/or electrocuted in the vault during the theft. 2.2 Units shall be guided by A.U.C For operational procedures for fires and emergencies in this type of installation. 2.3 Members are not to enter these vaults until Con Edison has made their examination. 2.4 Con Edison will make the determination that the vault is safe for entry, if necessary, by F.D. personnel. 2.5 F.D. personnel receiving this authorization will conduct a cursory search of the vault for victims. 6

7 REFERENCE # 2 (FORMERLY SAFETY MESSAGE # 56) Pole Mounted Transformers Con Edison does not test pole mounted transformers for PCB content. Almost all of Con Edison's overhead transformers are not, or were not, designed to be PCB liquid filled. They are mineral oil transformers. However, due to past storage and/or servicing practices some of these transformers have become PCB contaminated, i.e., PPM PCB. A small percentage of these transformers have attained levels of 500 PPM PCB or greater which classifies them as PCB transformers. All new transformers being installed by Con Edison as replacements for existing ones and/or new installations are non PCB transformers. All officers at operations involving overhead pole transformers shall insure that all proper precautions are taken to provide for the safety of all members on the scene as outlined in All Units Circular No. 266 (Revised) and Fire Tactics and Procedures, Hazardous Materials 2. 7