NORTH COUNTY FIRE AUTHORITY POLICY & PROCEDURE MANUAL OPERATIONS

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1 PURPOSE: To establish a policy to maximize safety and efficiency when responding to collisions/extrications/vehicle fires involving Alternative Fuel Vehicles. Hybrid (Gas/Electric powered) and Compressed Gas cylinders are of the most concern during these types of responses. POLICY: It is the intent of this operating guideline that fire department personnel shall operate at motor vehicle collision scenes within departmentally-defined safe practices, i.e. full turnout gear and SCBA. According to an MSDS-type information sheets available for Panasonic Ni-MH batteries, a battery fire will produce toxic fumes, including oxides of nickel, cobalt, aluminum, manganese, lanthanum, cerium, neodymium and praseodymium. Compressed Gas cylinders could present extra hazards as well. PROCEDURE - GENERAL: The goal for responders in securing the scene and providing a safe environment for rescue and incident stabilization is to satisfy the Four I s: Identify the vehicle is a Hybrid, Immobilize the vehicle, Isolate the power sources for the vehicle, and Inspect the vehicle for hazards. This is to be accomplished by satisfying the following tactical objectives (described in detail below): I. Identifying the Hybrid II. Preventing movement of the Hybrid III. Gaining access to the Hybrid vehicle s interior IV. Shifting the Hybrid s transmission into Park position V. Turning off the Hybrid s ignition switch VI. Ensuring the ready light is turned off VII. De-energizing the Hybrid s 12 volt electrical system I. HYBRID IDENTIFICATION A. Exterior Badges 1. Look for badges typically found on the vehicle s exterior in various locations. Examples for Ford, Honda, and Toyota/Lexus vehicles (respectively) are depicted below.

2 B. Visible Vehicle Components Generally bright orange insulation is used to cover the high voltage wiring. If seen, this may be reason to suspect the vehicle is indeed a Hybrid. Often the fact that it is a Hybrid is imprinted on the engine block. The C-pillar in some models (Toyota Prius) is vented to keep electrical system cool and is another identifying feature. C. Computer Software or other resources 1. Consult reference material (Holmatro, etc.) for assistance with identifying a Hybrid. 2. Most manufacturers produce an Emergency Response Guide (ERG) that will provide relevant information; many of these ERG s are included in the Appendix of this document as attachments. II. PREVENTING MOVEMENT OF THE HYBRID A. Chocking 1. Responders should remain away from the area directly in front of, and the rear of a Hybrid vehicle. 2. Responders should place wheel chocks of sufficient size and strength to prevent horizontal movement of the Hybrid vehicle. Generally it will be in front and rear of the tires. A minimum of two wheels should be chocked. III. GAINING ACCESS TO THE HYBRID VEHICLE S INTERIOR A. Access to Hybrid vehicle interior should be performed expeditiously.

3 1. Responders should avoid the Inflation Zone per SRS SOG (Remain 5 away from deployment path of side mounted SRS, 10 away from steering wheel mounted SRS, and 20 away from passenger s dashboard mounted SRS). 2. Once access into the passenger compartment is gained, ascertain the need for the operation of any electrically powered features of the vehicle and activate such features as deemed appropriate. For example, unlocking all doors, lowering all windows, and unlocking trunks or hatches. Responders should refrain from moving seats as the potential for SRS deployment exists. 3. Operate interior hood release mechanism to release hood if accessible. IV. SHIFTING THE HYBRID S TRANSMISSION INTO PARK POSITION A. Responders should attempt to place the Hybrid s transmission into Park position. Manually shift the transmission selector into Park position, or into gear if the vehicle is a manual transmission. B. Responders should apply the Hybrid s parking brake. V. TURNING OFF THE HYBRID S IGNITION SWITCH A. Locate and turn off the ignition switch. B. Remove the ignition key and place it a minimum of 50 feet from the Hybrid. Inform Law Enforcement of the key location. VI. ENSURING THE READY LIGHT IS TURNED OFF A. Most Hybrids are equipped with some form of indicator light showing vehicle is ready for operation. This is important in that the vehicle is virtually silent when starting up. Responders should look for such an indicator on the driver s side of the dashboard and ensure it is turned off. Generally turning off the ignition switch will turn the ready indicator off also.

4 VII. DE-ENERGIZING THE HYBRID S 12 VOLT ELECTRICAL SYSTEM A. Exterior Responders 1. Position a charged hoseline between the primary hazard and patients/rescuers. 2. Responders should remain to the side of a Hybrid to access the engine compartment. 3. Release the exterior hood safety catch and open the hood. Consider opening the hood in reverse fashion (nearer the windshield). Once the hood is opened; secure it in an open position. 4. Determine the location of the battery (ies). If the battery is not located within the engine compartment find the alternate location and gain access to the battery. Consider the use of available reference materials indicating battery and SRS locations (see Appendix). 5. Begin hazard mitigation activities if physical damage to the battery has occurred, i.e. electrolyte spillage. 6. Once the battery has been located and exterior responders are prepared to de-energize the electrical system, inform the interior responder(s) to coordinate the timing of shutdown. B. De-energizing the Electrical System at the Battery 1. Cut or disconnect the negative (ground) battery cable first using care not to touch any metal part of the chassis with the cable end or cutting tool. Do not cut any portion of orange high voltage harness anywhere in the vehicle. 2. If cutting the battery cable, cut the same cable twice to remove a 2 section. If you choose to disconnect the negative cable at the terminal, bend the loose cable end onto itself. Isolate the bare cable clamps from re-establishing a connection. Isolation can be performed with tape or even two exam gloves.

5 3. Ascertain if there is any evidence that electrical power from the battery is still supplying the vehicle. Look for lights remaining on (even if dim), horn working, chimes sounding, etc. 4. In a severe crash make certain that the battery case has not been penetrated by metal parts that could re-establish an electrical circuit. 5. To completely de-energize the electrical system, cut or disconnect all positive (hot) battery cables also. If you re cutting the cable, cut the same cable twice to remove a 2 section. Re-check the vehicle again to make certain that electrical power is not being supplied to the vehicle. 6. If the electrical system remains energized after these actions, determine the location of additional batteries and repeat the foregoing procedures. 7. Responders should look for any other source of electrical power, i.e. items plugged into lighter sockets for charging, etc. Note: Hybrid gasoline/electric vehicles pose no additional risks over a conventional vehicle if handled properly at an emergency incident. The electrocution hazard is removed because, by design, the 144-volt or 300-volt DC current is normally isolated from any contact with the vehicle itself. In order to receive a shock, an emergency responder would have to physically contact two separate points within the high-voltage system at the same time. If the parallel high-voltage cables running under the vehicle to deliver current to the front of the car were damaged as in a severe crash or fully involved fire scenario, the highvoltage battery would short circuit. This short would de-energize the entire high-voltage battery circuit. Hybrid Vehicle Suppression Policy: A fire involving a hybrid vehicle can be handled by following normal vehicle firefighting procedures, including: Fire is to be attacked with an adequate water flow rate (minimum 1 ¾ inch handline).

6 When water is used on a burning battery bank, some hydrogen gas may evolve. In this situation, ventilation by leaving the trunk or hatchback lid open is advised. If there is concern that hydrogen gas is present, fire smothering agents such as those used by hazmat teams should be considered. Foam should be considered for its smothering properties. Responders shall work from a safe position of approach (generally 45 degrees from each corner of vehicle). Self-contained breathing apparatus (SCBA) shall be worn throughout the fire incident. Wheels of the vehicle are chocked to prevent forward or rearward movement as soon as safely possible. In the case where the battery compartment has been breached, the following additional steps shall be taken by scene command: The vehicle shall be tagged by Incident Command as a potential hazmat safety concern. Command shall request from Fire Alarm that the vehicle be moved to a secured holding area. Fire Alarm shall alert the local dealership (Ford, Honda, Toyota, Lexus) of this incident to request proper battery disposal to be completed by an authorized battery recycling agency. Note: Most hybrid vehicles employ a bank of Ni-MH (Nickel Metal Hydride) batteries located in the rear of the vehicle. In the Ni-MH Product Safety Data Sheet from Moltech Power Systems, responders are advised that virtually all fires involving Ni-MH batteries can be controlled with water. This information sheet also recommends, In case of fire where nickel metal hydride batteries are present, apply a smothering agent such as METL-X, sand, dry ground dolomite, soda ash, or flood the area with water. A smothering agent will extinguish burning nickel metal hydride batteries.

7 Appendix Supporting Documentation: Manufacturer Emergency Response Guides for Major North American Hybrid Automobiles A. Ford Escape B. Honda Civic C. Honda Insight D. Lexus G450h E. Lexus RX400h F. Toyota FCHV G. Toyota Prius ( First Generation Prius) H. Toyota Prius 2004-date ( Second Generation Prius) I. Toyota RAV4 Compressed Natural Gas Properties (CNG): Compressed to 3600 psi in fuel cylinder CNG rated at 117 octane fuel BTU per lb. = 22,800 ( gasoline = 18,900 Not a liquid when compressed; it becomes a very close dense gas Not the same as Liquefied Natural Gas; LNG is a cryogenic and at -260 degrees to become liquefied. Lighter than air when released LEL / UEL = 4-16 % (gasoline = %) 1 cubic foot of CNG = 245 cubic ft. of natural gas at sea level (uncompressed) 1 cubic foot of CNG weighs 13 pounds (5.66 pounds = 1 gallon of gasoline equivalent (GGE Honda Civic Tank = 8 GGE Note: 1 gallon of gasoline properly vaporized has the explosive equivalency of 83 pounds of TNT.

8 Cylinder Properties- 4 Types 1. All Metal (steel or aluminum) 2. Hoop wrapped steel or aluminum 3. Fully wrapped steel or aluminum 4. All composite (non-metallic) *Early model Honda Civic uses Type 4 Note: The PRD (pressure relief device) activates similar to a fusible link (it fails versus resealing like a spring-assisted pressure reducing valve-prv). The gas is vented

9 out the vent tube until the tank is empty. Discharge time depends on the fuel level. Lessons Learned / Best Practices Approach from a 45 degree angle to vehicle ends. Be aware of CNG vehicles-cabs, City Vehicles, Shuttles, Buses. Look for CNG placards. Watch for other hazards-bumper struts, hood and tailgate struts, airbags, burning fuel runoff, hazardous vehicle contents, ignited tires, etc.. Consider cooling streams from a greater distance in fully engulfed CNG vehicle fire. Secure enough water supply in the event of using cooling streams.