On Thursday October 2, 1997, two Carthage, Illinois Fire Department volunteer
firefighters died, one was seriously injured, and another was injured when a horizontal
liquefied petroleum gas (LP-Gas) tank BLEVE’d (Boiling Liquid Expanding Vapor Explosion).
The rocketing tank struck them as they prepared to advance pre-connected hoselines
from their high-pressure fog pumper about eight minutes after their arrival. The first fire
company to arrive on the scene to a reported dryer fire found not only the grain dryer fire
but also 30 to 40 foot intermittent fire plumes from the safety relief valves on two 1,000
gallon LP-Gas tanks, and a fully involved field tractor. Deciding on a direct attack, the
first-in fire officer positioned the engine and firefighters behind a large grain silo 100 feet
away from the burning tanks. But the engine’s tailboard extended beyond the silo’s vertical
edge and was nearly inline with the end of one of the tanks. Three of the firefighters were
advancing around the rear of the tailboard when a large tank section struck them.
The death of these firefighters demonstrates the serious hazards firefighters face
when attacking LP-Gas tank fires. The need for first-in fire officers to be well trained in
hazard and risk analysis and their ability to formulate effective action plans is critical to safe fireground operations. In many cases, LP-Gas incidents require the first-in officer to
evacuate the area in anticipation of a tank failure rather than placing firefighters in position
to try and prevent the failure. Analysis of the fireground factors present at the time
of this incident indicate the chance of a successful direct attack to cool the tanks was
unlikely given the severity of the fires.
The decision to make a direct attack is especially critical when an incident exceeds
the capabilities of the initial crews to stop an escalating situation due to a lack of
on-scene resources. In this incident, an immediately available and sustainable water
supply for large volume hose streams was not rapidly obtainable. Even with an adequate
water supply, firefighters may not have been able to apply the water with enough volume
quickly enough to cool the tanks and relieve the excessive pressure before a failure
occurred. The fire had been heating the tanks for over ten minutes and there was possible
flame impingement on the top of the tanks.
When attack decisions are made, firefighters’ position relative to the ends of the
tank is critical. The Fire Chief knew that horizontal LP-Gas tanks fail and generally
rocket in the direction parallel to the long axis of the tank and was working to avoid the
ends. Firefighters located at the end of an LP-Gas tank are subject to being struck by the
tank if the tank fails as this incident demonstrates. An additional concern over tank
failures is the release and ignition of the liquefied gas, which quickly flashes to vapor and
the energy released, can seriously burn or kill even fully protected firefighters. At this
incident, the firefighters suffered no thermal injuries, but their intermediate stopping
position in line with the tank’s end reinforces the tactic that tanks should only be approached
from the sides.
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