Using Nozzles Effectively On 1 1/2-lnch Hand Lines
The Volunteers Corner
There are a number of different variations of fog nozzles for 1 1/2-inch hand lines, but on the foreground the biggest difference in their effectiveness is probably the competence of the nozzleman.
How well he does his job determines how quickly he darkens down the fire and then completes extinguishment. The efficiency of the nozzleman also will influence the amount of water damage and how effectively the line advances.
If the fire is within the capability of a 1 1/2-inch line attack, the nozzleman must select a nozzle that will discharge enough gallons per minute to rapidly extinguish the fire. Otherwise, the officer should have started the attack with a 2 1/2-inch line—or even master stream equipment.
Everyone wants to prevent water damage by avoiding an unnecessary application of water. However, it is well to remember that one of the best ways of avoiding water damage is to extinguish the fire quickly. There is bound to be an increasing amount of water damage, up to a point, as the fire continues to burn beyond the time when it should have been extinguished by an effective attack using the necessary rate of water application.
The reason I threw in the “up to a point” in the last sentence is because no one complains about water damage in a total burnout.
Variable gallonage nozzles: When the nozzleman uses a variable gallonage nozzle, he must make certain that the gallonage he wants to use is the one he sets on the nozzle— even in the dark. By experience, he learns to recognize how many gpm a fire requires for extinguishment and he gets the feel of how quickly the fire should be darkened down.
If the nozzleman selects a gpm setting below the maximum for his nozzle, he should quickly go to the higher gallonage when the fire does not diminish quickly. If he doesn’t do this, his officer on the line should order him to increase the gpm. The officer should watch the results closely and be quick to inform his superior officer when a larger line is needed.
Constant gallonage nozzles, of course, provide only one water application rate when the shutoff is fully open. So any variation in the flow rate can be in only one direction— downward. But this can be a handy thing to know many times.
Once the fire is darkened down, you may require less gpm for overhaul and final extinguishment. With a variable gallonage nozzle, it is easy to turn the selector to a lower gpm rate, but the same thing can be accomplished with a constant gallonage nozzle by slowly choking down the shutoff until the nozzle is flowing the desired amount of water.
Cracking open the shutoff: When a nozzleman enters a smoky room with a high gallonage nozzle and finds that all he has to extinguish is a smoldering fire in an upholstered chair, it is easy enough for him to crack open the shutoff just enough to flow sufficient water for extinguishment without spraying a large area. Any nozzle will flow as little as a few tablespoonsful of water a minute if you just barely crack open the shutoff.
There are some nozzles in the fire service that provide a choice of two gpm rates. Every nozzleman who may use such nozzles should become thoroughly familiar with the control device and learn to recognize the stream size for each gallonage. Learn this so well that even at night or in thick smoke you won’t be applying the lower gallonage when you think you are getting the larger flow.
Automatic nozzles will maintain a constant nozzle pressure within upper and lower gpm limits for each type nozzle and the nozzleman can vary the flow rate and maintain an effective fog pattern by varying the shutoff opening within these limits. If the shutoff is choked down too much, the fog pattern will suffer, but there are times when this does not matter because only a small application rate is needed to complete extinguishment of smoldering material close at hand.
Because fog nozzles don’t have as much reach as straight tips, hose crews must move closer to the fire. There will be times when the heat will become too much for the hose crew to maintain their position, but the nozzleman can sometimes alleviate this situation by directing his fog stream overhead for a couple of seconds. Sometimes this is all it takes to cut the temperature just enough to continue the attack on the fire and further reduce the heat by knocking down the fire.
Nozzle gives protection: If retreat is necessary, the nozzleman must remember that the nozzle provides protection for the hose crew. By directing the fog cone into the upper part of the area, the nozzleman can set up a defense against superheated gases—or flames—swirling overhead and dropping down on the hose crew..
The nozzleman must fit the fog pattern to the situation when he is using a variable pattern nozzle. The widest pattern offers the most protection to the hose crew, but it may not reach the body of the fire. So the nozzleman must use judgment to select a pattern that protects his crew and at the same time puts the water where it is extinguishing the fire. Because the officer is No. 2 man on the line, he has a better view of the fog cone and what it is hitting, so he should use this information to guide the nozzleman to a more effective attack.
As we said in the beginning, an effective attack is the answer to all our problems. Once you extinguish the fire, your problems become minimal—and you have plenty of time to consider them.