Event Description A full response was dispatched for a report of a structure fire. Crews arriving encountered heavy smoke in the area and had to approach the scene slowly to identify which structure was on fire. There was a breeze blowing that lifted the smoke briefly to reveal a large, wood frame, vacant structure, well involved, threatening exposures on the Bravo and Delta sides. The first arriving unit, a ladder company, established command and called for defensive operations. I was working in the command post with the IC. We both noticed through the thick smoke that the house service from the pole to the structure began to arc at the pole. The line arced twice and before we could issue a warning, dropped into the street. Crews had also heard the lines arcing and began running from the area before the line dropped. The line bounced off of one of the engines, laid across several attack lines and came to rest in a pool of water. A company officer contacted command and advised the downed line was lying across attack lines and in the pool. The IC rebroadcast the warning to all personnel and assigned one of our training officers as a lookout to warn people away from the line. Barrier tape was also put in place to prevent people from coming in contact with the line. Crews worked around the downed line until the power company arrived and dropped the fuse at the pole. #11-343
Lessons Learned The most significant lesson here is to not take anything for granted. The involved structure was boarded up and had been vacant for several years. It was in a severe state of disrepair and heavily involved when companies arrived. Thick, heavy smoke was blanketing the area when the crews arrived. The smoke conditions and condition of the structure masked the fact that the power was still hot to the building. When the service became involved, it burned and separated from the house quickly. Crews on the ground could hear the arcing, but only those operating outside of the smoke plume could see the arcing. The IC and advisor saw two quick arcs, with accompanying buzz, as the smoke cleared. The line dropped before anyone could give warning. Command may want to consider assigning an additional safety officer for defensive operations at large structures. Companies noting vacant and abandoned structures in their areas should notify their building officials and utility companies to pursue disconnecting utilities from the structures.
Discussion Questions 1.Once the electrical hazard is identified, what resources can you use to assist in rendering the site safe? 2.Chief Officers, how would you adjust your tactical plan to maintain the safety of the crews on scene? 3.Company Officers, how will you relay the emergency warning to ensure all of your members are aware of the downed wire? 4.Driver/Operators, what new challenges are you now faced with, having a downed power line across your supply or attack lines? 5.Fire fighters, once identified, what are the hazards inherent with a situation like report 11-343? #11-343