Fire; Overhaul - Lexus GS 450h Manual

Emergency Response (Continued)

Fire

Approach and extinguish a fire using proper vehicle fire fighting practices as
recommended by NFPA, IFSTA, or the National Fire Academy (USA).
•
Extinguishing Agent
Water has been proven to be a suitable extinguishing agent.
•
Initial Fire Attack
Perform a fast, aggressive fire attack.
Divert the runoff from entering watershed areas.
Attack teams may not be able to identify a GS450h until the fire has
been knocked down and overhaul operations have commenced.
•
Fire in the HV Battery Pack
Should a fire occur in the NiMH HV battery pack, attack crews
should utilize a water stream or fog pattern to extinguish any fire
within the trunk except for the HV battery pack.
WARNING:
•
The NIMH battery electrolyte is a caustic alkaline (pH 13.5)
that is damaging to human tissues. To avoid injury by
coming in contact with the electrolyte, wear proper personal
protective equipment.
•
The battery modules are contained within a metal case and
accessibility is limited.
•
To avoid serious injury or death from severe burns or
electric shock, never breach or remove the high voltage
battery pack cover under any circumstance including fire.
When allowed to burn themselves out, the GS450h NiMH battery
modules burn rapidly and can quickly be reduced to ashes except for
the metal.
Offensive Fire Attack
Normally flooding a NiMH HV battery pack with copious amounts of
water at a safe distance will effectively control the HV battery pack
fire by cooling the adjacent NiMH battery modules to a point below
their ignition temperature. The remaining modules on fire, if not
extinguished by the water, will burn themselves out.
However, flooding the GS450h HV battery pack is not recommended
due to the battery case design and location preventing the responder
from properly applying water through the available vent openings
safely. Therefore, it is recommended that the incident commander
allow the GS450h HV battery pack to burn itself out.
Defensive Fire Attack
If the decision has been made to fight the fire using a defensive
attack, the fire attack crew should pull back a safe distance and allow
the NiMH battery modules to burn themselves out. During this
defensive operation, fire crews may utilize a water stream or fog
pattern to protect exposures or to control the path of smoke.

Overhaul

During overhaul, immobilize and disable the vehicle if not already done. See
illustrations on page 17. The HV battery cover should never be breached or
removed under any circumstances including fire. Doing so may result in
severe electrical burns, shock, or electrocution.
•
Immobilize Vehicle
Chock wheels and set the parking brake.
Move the shift lever to the Park position.
• Disable Vehicle
Performing any one of the following three procedures will shut the
vehicle off and disable the HV battery pack, SRS, and gasoline fuel
pump.
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