We have all heard it before, fog vs. smooth bore. The arguments for both sides have been going on for ever. The pro’s and con’s of each are getting longer and longer. Which ever camp you belong to, I am sure you are confident in your argument and have many justifiable reasons that you believe what you believe. With that said, I am going to attempt to settle the debate once and for all! Here we go…
Let’s first break it down to a simplistic form. A firefighting nozzle is simply a device that we use to shape and direct water from a hose line. Based on the size of the orifice and the design of the nozzle itself, we can use pump discharge pressures to determine just how much water comes out of the end and to us that is extremely important, since GPM puts out fire, not PSI.
Now that we understand a fire nozzles job, we must understand that each type of nozzle is DESIGNED for a specific job, specifically producing a certain type of water pattern and shape as it leaves the nozzle on the way to the fire. A fog nozzle is designed to break the solid stream of water from inside the hose into tiny drops and a a smooth bore nozzle is designed to leave the solid stream of water intact. With each type of nozzle designed for a specific purpose, then wouldn’t it be easy to choose the right nozzle for the job based on the type of job we are doing?
Nozzle selection should be simple. You should choose a nozzle based on the type of fire attack that you are choosing to use. End of story. If you choose to want to use indirect attack to extinguish a fire, the best choice for the job is the fog nozzle, since it is designed to produce small drops of water which are needed for indirect attack. If you are choosing to use direct attack, then the best choice is to use a smooth bore nozzle since it is designed to deliver a solid slug of water, and that solid stream best gets to the seat of the fire. If you want to use both methods then only the fog can do both, although it is not as good at direct attack since the stream it produces is broken. If you are concerned about air movement and pressurization of the fire compartment, then choose a smooth bore since a fog nozzle moves a much larger amount of air and produces an inward air flow.
We can end this great debate if we stop trying to say which nozzle is best, since they are both have a specific purpose, and Instead choose which method of fire attack is best for the given situation, and then nozzle choice becomes automatic.