Brennan Q&A April 2005

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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.

APRIL 2005

Question: We are a medium-sized, paid, on-call department, that has in the last year gone through some big changes. We have some very progressive people and a new chief ( hired from outside), who is open to most of our ideas. We are three fire departments consolidated into one. One of them, I would say, is much more progressive than the others. Some of us are very interested in implementing smooth-bore 1¾-inch hand lines on preconnects. The station that wants it has three 1¾-inch lines to work with, while the others only have two and are less likely to go along with the idea. What are some ways we can sell this to get everyone comfortable with using smooth-bore, when all they think works is combination nozzles? Thanks for your time.

Answer: Hey listen, brother. What works is a well-trained, well-drilled, professional quality team that forms to stretch the proper size hose for the proper length to the best place, with enough hose (smoothly) stretched to "finish" the tactic you are attempting. That is what works when it is good and what doesn't when it is bad. No nozzle, pattern, distribution or shape of drops of water ever made a great engine poor or a poor engine good. With that said, remember that purpose of water for extinguishment is to cool the fuel source sufficiently so that it no longer is at its ignition temperature and the gases given to the fuel supply are shut down (are no longer produces).

Where does the hose stream lose its full (100 percent of engine) discharge? Possible causes include defects in the nozzle controls, poorly maintained nozzle openings (solid stream), break-up of the stream too early (faulty nozzles of solid stream and non-effective fog drops in the periphery of a poorly selected nozzle cone pattern). Having the cooling water change to steam at the hottest part of the flaming is ideal cooling. Having the water vaporize on the way to the target is less effective, to say the least. The larger the "slug" of water, the more it will get through the heat to the target. The best (most effective) hose line will deliver 85 percent of its supply from the nozzle in a 15-inch circle at the fuel! How you do that is your business!

I really am tired of the nagging argument or discussions about the type of nozzle to use. The real issue is the type of stream that is being played on the fuel (heated combustibles). Take the size hose line that you need to "make" the fire floor. Remember that line smaller than 2½-inch cannot hold anything and must move forward constantly for interior structural fire operations. No nozzle will make up for the poor selection of size and amount of hose for the tactic chosen.

Now once you have that down, work with your nozzles and determine which lets you do the best job. One caution, however. Remember that fog-type nozzles are designed to maintain the same nozzle pressure (therefore range of stream) through a great variety of amounts of water. It is hard to realize when you are running out of water or don't have enough in the first place. I upset a lot of people with that sentence, but they are not ever found in my "hallways."

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Write if you agree or don’t agree or on anything. Tbrennan@firenuggets.com

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