A five -alarm fire on Sunday March 10, 2013 resulted in several firefighters nearly losing their lives, when a resulting backdraft or smoke explosion rapidly occurred during fire suppression operations in a mixed use occupancy building in Harrison, New Jersey.
According to published reports, the rapidly extending fire likely started in the kitchen of a Mexican restaurant on the 600 block of Frank E. Rogers Avenue before it quickly spread and engulfed the entire building, and the adjacent exposure.
Reported information states Investigators have stated this is the second time a fire has broken out in the restaurant.
Fire Department officials have initially classified this as a backdraft as first published in the media. “The unfortunate thing with a back-draft is that initially there’s heavy smoke in the building,” said Captain Robert Gillen of the Harrison Fire Department, “all you need is an entrance of more oxygen and there’s a massive explosion.” Two of the firefighters had more extensive injuries than the other three.
A series of video screen captures has been developed to clearly depict the sequence of events that were apparent as the smoke conditions between the fire building and exposure occupancy rapidly and in a quick succession of seconds went from showing normal fire suppression operational smoke profiling to what would become a backdraft [like] explosion or smoke explosion affecting numerous operating interior and fireground companies.
The need to maintain concise and focused situational awareness during all phases and stages of fireground operations is imperative to identify conditions when subtle or rapidly changing situations and environments may present an opportunity to communicate and react accordingly.
It’s readily apparent that the rapidness of the smoke changes and pressures that can be seen dramatically sequenced into the explosion stage with little chance to initiate actions.
It should be noted that the brief series of frames in the video can not fully ascetain if this is truly a backdraft explosion or a smoke explosion. There are sublte differences in the intiating fire dynamics and sequence of events interior events.
The importance of understanding the building, the occupancy risk and the manner in which fire and the products of combustion typically travel within similar or unique occupancies and the manner in which commanders and officers monitor and maintain keen situ-awareness.
Recognizing fire behavior indicators and monitoring fire dynamics within the fire compartment and building envelope and the impact of fire suppression actions and intervention and external environmental factors require frequent monitoring and peridic status reports to maintain fluid and continuous assessment of conditions that may influence the conduct of operations.
This event continues to reinforce the need to never allow complacency creep to occur regardless how predictable or unchanging the commonality of the operations are being undertaken or conducted, in similar fashion to past successes in comparable occupancies and structures.
- PHOTOS: http://abclocal.go.com/wabc/gallery?section=news&id=9022314&photo=1&pid=9022222
Training Links (compiled courtesy of Firefighterclosecalls.com and the Secret List)
- POWERPOINT 1-The Art of Reading Smoke PPt from Dave Dodson: http://www.firefighterclosecalls.com/news/fullstory/newsid/106558
- POWERPOINT 2-The Art of Reading Smoke-Sequel from Dave Dodson: http://www.firefighterclosecalls.com/news/fullstory/newsid/68508
- Smoke Explosions-Paul Grimwood: http://www.firetactics.com/service.htm
- Backdraft/Flashover-The Difference-Vincent Dunn: http://vincentdunn.com/dunn/newsletters/dec/dec.pdf
- Smoke Explosions-Ed Hartin: http://cfbt-us.com/wordpress/
- Dave Dodson Video: https://www.youtube.com/watch?v=l8CxxwD0Ir8
Check out the link and Follow-up discussion from Chief Ed Hartin (link HERE)
Reading the Fire
Before watching the video (or watching it again if you have already seen it), download and print the B-SAHF Worksheet. Using the pre-fire photo (figure 1) and observations during the video, identify key B-SHAF indicators that may have pointed to potential for extreme fire behavior in this incident.
Important! Keep in mind that there is a significant difference between focusing on the B-SAHF indicators in this context and observing them on the fireground. Here you know that an explosion will occur, so we have primed the pump so you can focus (and are not distracted by other activity).
Backdraft or Smoke Explosion
While smoke explosion and backdraft are often confused, there are fairly straightforward differences between these two extreme fire behavior phenomena. A smoke explosion involves ignition of pre-mixed fuel (smoke) and air that is within its flammable range and does not require mixing with air (increased ventilation) for ignition and deflagration. A backdraft on the other hand, requires a higher concentration of fuel that requires mixing with air (increased ventilation) in order for it to ignite and deflagration to occur. While the explanation is simple, it may be considerably more difficult to differentiate these two phenomena on the fireground as both involve explosive combustion.
- Did you observe any indicators of potential backdraft prior to the explosion?
- Do you think that this was a backdraft?
- What leads you to the conclusion that this was or was not a backdraft?
- If you do not think this was a backdraft, what might have been the cause of the explosion?
For more information in Backdraft, Smoke Explosion, and other explosive phenomena on the fireground, see: