Brennan Firepics Comments 6

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TOM BRENNAN has more than 35 years of fire service experience having responded to 33,000 fire alarms. His career spans more than 20 years with the Fire Department of New York as well as four years as chief of the Waterbury (Conn.) Fire Department. He has a bachelor of science degree, summa cum laude, John Jay College; Alumnus of the Year Award, John Jay College; chairman of the Connecticut Fire Chiefs Association and a charter member of the National Fire Protection Association, Fire Service Section. He has delivered courses and seminars throughout the United States and has instructed at the National Fire Academy. He was the editor of Fire Engineering Magazine for eight years, is currently a technical editor, and his column “Random Thoughts,” is a regular monthly feature. He is co-editor of The Fire Chief’s Handbook, Fifth Edition. He is the recipient of the 1998 Fire Engineering Lifetime Achievement Award.

FIRE IN A COMMERCIAL ESTABLISHMENT

This photo appears to be a “routine” fire that occurs in every district throughout our land. So what is there to talk about?

Well, what is on fire? A commercial occupancy within a strip store, you say. But is it? One of the size-up points of these fires is to locate the firewalls, if there be any. They impact the size of the manageable fire area for the moment of arrival. In short, the firewall will limit the probable horizontal spread of fire.

The store on fire is definitely higher than the exposure (D or 4) and the photo thus indicates that the firewall is in place and isolating this occupancy.

So the fire as it appears on arrival is not a typical strip-store or taxpayer fire. The store is on a corner, and this limits exposure problems with regard to the logistics and manpower needs — and, indeed, cuts them in “half.”

Second blessing here is the firewall. So instead of a fire in a multi-occupancy strip store, we have a fire in a one-story 40' x 80' commercial occupancy.

Second lesson is the position of the portable ladder to the roof of the exposure. It is intended to get the vertical ventilation team to the roof and, as such, is in a safer position than if it were placed on the fire occupancy. Ladders to roof areas should be placed as remote as practical from fire exposure.

Next is the parapet wall. Remember, parapet walls are walls standing on walls, with the poorest of support assemblies. This one is also supporting an additional load of the decorative mansard look. It is probably nothing but a heavy void space. Collapse of this wall is not imminent here, but it is a factor to consider at command.

Second impact of this parapet construct: If this structure was the target for the roof team, how would they get down from the ladder device that they raised to get there?

“Jump,” you say, “they are firefighters!” Well, this multi-impact load of 300 pounds each is not what the roof was designed to take. It prevents the team from “feeling” for the remaining strength of the roof.

Next: How do they get up to the ladder device to escape or take up? How do they get all the tools in place or back to the street? And, on the side: If this were a defensive attack with collapse potential, are these firefighters safe?

No! They are in the collapse zone of this structure. Apparatus is moved and the firefighters have crept back into the potential area of collapse debris. At single-story fires, a rule of thumb is that the sidewalk AND the parking lane are always in the collapse zone.

See ya another time.

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