This is in reference to Jerry Knapp`s comments in Letters to the Editor, April 1996, regarding the superiority of smooth-bore nozzles for interior fire attack…. It is true that smooth-bore nozzles have a place and function for fire extinguishment or overhaul, but the utilization of smooth-bore nozzles can compromise the safety of interior fire suppression crews.
It appears Knapp`s opinion on the use of smooth-bore nozzles is based on training scenario sessions with concrete burn buildings and limited, controlled fuel sources. In the real world, fire attack crews advance lines into buildings not designed to be on fire and loaded with fuels that produce significant Btus during combustion. The limited surface area of the smooth-bore nozzle stream does not allow for rapid cooling of the fire gases nor does it provide any thermal protection for the crews if required.
I agree that the attack method of swirling the combination fog nozzle is not the best utilization of the tool and can create an uncomfortable condition he describes as “fireman`s soup.” I suggest that applying fog into the ceiling area for a few seconds and the straight stream directly to the remaining fire would produce better results and eliminate the soup. The droplets at the ceiling area expose the maximum surface area of the water, which allows the hot gases to cool rapidly, thus creating a more tenable and safe environment. With a little practice, you will discover that the thermal balance is maintained and visibility is not diminished. As a chief, my comfort level with the attack crews` safety would be greatly diminished if I depended on smooth-bore nozzles for their protection while conducting interior fire attack.
As far as revisiting your SOPs to utilize your stream for ventilation, the fog stream can and does provide some immediate ventilation while other crews put different devices in service and, in my opinion, should be encouraged when circumstances dictate.
I would encourage all to experiment with all the different water application tools and decide for themselves what they believe provides the best and safest fire stream.
William C. Kelly, CFPS
Fire Chief, Instructor
Claymont, Delaware
