To further emphasize the dangers firefighters are exposed to operating in battery rooms protecting tenants’ hardware in high-rise commercial buildings, I am focusing on two recent incidents in a major U.S. city. In the first incident, a power company worker came across a battery fire in their own equipment room. He grabbed the nearest fire extinguisher, a C02, and attacked the single involved wet-cell battery. The “thermal shock” from the extremely cold C02 agent hitting the battery string caused the involved battery and the batteries immediately to the left and right to experience a split in their jars/casings, spilling their contents out onto the floor and splashing the boots and pants of the worker. He immediately left the area and quickly removed the articles of clothing affected and ensured that no acid (sulfuric) had come into contact with bare skin. He luckily escaped serious injury and disfigurement.
In the second incident, the fire department responded to a battery room where several batteries were melting down (the majority of the batteries can literally vaporize during this process). The crew’s CO monitors began activating, so they withdrew to don their self-contained breathing apparatus (SCBA) and went back in to address the battery fire while power was being turned off to the UPS system by on-site technicians. The gas that triggered their alarms most likely was hydrogen gas, not CO. Note: Hydrogen gas may be present in its raw form, which is odorless, and hydrogen sulfide gas, which smells like rotten eggs, also may be present. Although there may have been a small amount of CO present from the fire/meltdown, there was a very high probability that the crew was standing in a pocket of flammable/explosive hydrogen gas that is even more volatile than CO, which can also ignite (i.e., backdraft). The crew may have narrowly avoided a catastrophe by sheer luck, where conditions were not quite right for ignition.
It is vitally important to remember the dangers of battery room incidents. As noted in my first article on redundant power supplies (Firehouse, August 2005), avoid using C02 extinguishers in close proximity to batteries in attempting extinguishment of battery fires due to the “thermal shock” effect. Also, be very aware of the accumulation of explosive hydrogen gas and lead acid mist during battery fires and the possible absence of proper room ventilation, which may increase the risks to fire crews operating in the area (explosion and heavy metals exposure).
Also, remember that it is allowable by code to designate the entire battery room as a spill containment area, if one or more jars may fail and release their acid solution. This presents very high levels of risk to crews entering the room to investigate an incident. If a loud whistling noise is heard upon entering the room, vacate immediately, as an explosion may be imminent due to thermal runaway.
Lastly, always make a quick check above the fire floor in a high-rise fire to determine if there is a battery room directly above the fire area. The significant concentrated weight load may result in a premature floor failure. A catastrophic pancake collapse of floors all the way down to and below grade level is possible.
As these battery rooms become more prevalent as fewer and fewer companies wish to risk power loss, over time they will present themselves as a firefighter threat in the same realm as truss construction. Incidents will increase, as will near misses…and tragedies. Be safe and as the late, great Frank Brannigan preached religiously, “Know your buildings”