MYTHS AFFECTING SAFE AND EFFECTIVE HOSELINE USE
RANDOM THOUGHTS ON…
We are sometimes trapped into operating less than effectively because of rumors, half-truths, and untruths-myths. They surround much of what we do in the fire service. They are usually masked over by “blankets” called tradition or innovation. Here are some that affect our extinguishment success-the supply and use of hoselines.
A small-diameter hose pack is sufficient for high-rise firefighting. Before you get in an uproar, let me say that this is true 90 percent of the time. Most of our high-rise experiences are hot, smoky nuisances: rubbish in the service elevator lobby, a computer room, electrical motors and transformers. But then there’s the 20,000-square-foot (or more) inferno-threatening to wrap the core and extend by autoexposure to higher football field-size floors. And because of luck in this country, we haven’t had the thousands of exposed civilians to protect.
Ask a fire officer if he would stretch a preconnect into a fully involved supermarket. If he is experienced, flexible, and success-oriented the answer should be, “No. 1 need something larger.” Well, at that small percentage of high-rise fires you have the equivalent of two plastic-loaded, fully involved supermarkets hanging 200 feet or more in the sky on each fire floor.
Bigger pumpers mean more water. As it stands, this is a true statement. One author wrote in his manuscript that small, rural, understaffed departments should invest in pumpers with a capacity of 1,500 gallons per minute or morel This pumper at capacity (160 psi pressure) will supply six or more 2‘/2-inch handlines. Tlie number of personnel required to handle this is between 18 and 24 firefighters. Can you get 1,500 gallons from your water source? Large-caliber master streams should be supplied from more than one source. And while we re at it: No foreground commander at an escalating fire (six handlines) wants the water supply from a single source, nor should any firefighter.
Large-caliber aerial streams should deliver 800 to 1,000 gallons per minute. Another halftruth-the word velocity is missing. If this is for an agressive, defensive firefight (no collapse factors), then choosing nozzles and patterns (especially for tower ladders) also counts. When the firefight goes from offensive to defensive and you bring in the aerial guns, personnel (the life hazard) should be withdrawn. These streams should operate close to the building openings, at window sills attacking fire, blasting down ceilings, and poking through partitions. That needs hitting power-narrow patterns or solid-stream nozzles at high velocity. A highly maneuverable, aggressive tower ladder should finish the job. Rarely should firefighters have to reenter the disastrously weakened structure.
Variable-pattern (fog) nozzles as opposed to the use of solidbore (open) nozzles has been the subject of recent discussion. A smile comes to mind because both have been around for so long. The value for each lies in the tactics based on the size-up you use and not the nozzle. If the firefighting units maneuvering the handline are aggressive and can reach the seat of the fire at an occupied building before opening the nozzle on the handline, then the straight-stream pattern should be employed. The solid stream, in my experience, is more effective at that time than the straight, hollow stream of the variable-pattern nozzle. However, if advance is slow and through superheated atmospheres on the brink of flashover or rollover, then variable patterns may be more effective and safer.
In short, if you plan to open the nozzle and advance on smoke, use the variable pattern. If you have rapid advance tactics and a backup relief crew standing by, the solid nozzle has the advantage.
Again-only my opinion.