Saturday, April 13, 2013
Commercial Building Fires - Some Thoughts
For the purposes of this weeks review we will define this topic as any of the following: mercantile, business, industrial buildings. Supermarkets, department stores, shopping centers, doctor's offices, business offices, factories and manufacturing.
Things to consider:
Firefighter Safety
In addition to all normal considerations of safety, the size and area will pose greater accountability problems as well as greater fire volume problems. Access and entry points should be monitored closely. There should be multiple rapid intervention companies available on different sides of the building, but certainly the point of attack and any area that may give alternative access. Sprinklers operating will deteriorate visibility considerably. High rack storage poses a possibility of collapse and entrapment. Extremely high interior ceiling heights can mask the extreme heat buildup of flashover.
Search & Rescue
Search and rescue in these buildings will be extremely labor intensive and problematic. This is not like searching a residential occupancy. People that are in these structures tend to enter by the entrance they usually use. This can be of some assistance to firefighters searching. Time of day is also significant as occupancy may be low or non-exisitant.
Exposure Protection
In strip malls and downtown areas exposure protection can be a real challenge. Downtown business districts have buildings with apartments above (internal exposures) and close buildings (external exposures). In strip malls common ceiling attic or basements areas can lead to very serious fire spread horizontally.
Extinguishment
Use large volumes of water and the needed rate of application. 7 1 3/4 " lines is not always equal to an appropriate number of well placed 2 1/2" lines or master streams. Large volumes of stock piled material will add a significant fuel load. Also consider standpipes if avaialbe and do not fail to supply the existing sprinkler system.
Ventilation
While commercial buildings tend to have a lot of roof openings opening up can be difficult. Consider the use of positive pressure ventilation if you have the ability and the training to do so.There has been a lot of talk about trench cutting roofs. Trench cutting is a valuable tactic for preventing horizontal spread but it does take manpower and resources and a little bit of time to achieve.
Overhaul
Overhaul in commercial fires can be very dangerous and time consuming. After fire has been knocked down, you should consider letting the building drain for a brief period particularly if large caliber streams have been used. Rotate crews often, keep ventilation going to prevent smoldering buid up of carbon monoxide and other toxins.
Salvage
Commercial occupancies present the greatest potential for salvage if you have the manpower and resources to do it. Any valuable stock or products that can be saved from fire water and smoke damage will be greatly appreciated. I am not saying now, and will never say risk your life for property, but if you can operate in an area remote from the fire, or floor below than you should make an attempt to safely do what you can WITHOUT RISK TO PERSONNEL.
Take these pointers, review them with your troops and go and preplan one of your own buildings in your community all the time thinking about these points listed above.
Also contact someone to obtain a good Firefighting Tactics and Strategy Book such as the one published by Delmar Publishing or John Norman's Handbook of Tactics.
Thanks and stay safe, and stay thinking!
Pete Lamb
Copyright 2013