How quickly can your crew set up a foam operation? For this article, I am talking about trucks (standard pumpers) that have foam containers and a foam eductor attached to a discharge gate. I am not talking about trucks that have foam piped into their systems.
With that said, you still need to drill and exercise your system on a regular basis — whatever system that may be. You will do more harm than good if you just let it sit and never do anything, expecting it to work when needed.
As with many things in the fire service, it is best to expect the unexpected. You may not think you need foam, but establishing a quick connection may make the difference in getting a fire under control. At any given moment, a simple car fire can turn into a fuel fire. A generator on a trailer behind a utility truck can quickly turn bad if the fuel tank is compromised.
As we all know, it takes some time to set up a foam operation. You need to have the AFFF foam containers close by for easy access, along with the foam eductor. The foam eductor tends to get neglected, so check it on a regular basis.
Assure that the metering valve is well lubricated and turns and locks at the different settings. It also needs to be well-marked. The numbered reference for the metered concentrations that goes around the area below the valve has a tendency to get scratched and/or wear off. Also, assure the check ball inside moves freely or rattles when shaken.
My department carried three five-gallon containers of AFFF (15 gallons total). As most of us know, you can use these foams at a 3 percent (petroleum-based) or 6 percent (polar solvents) concentration.
So let's do the math: If pumping from a 500-gallon tank and flowing foam at a 3 percent concentration, the 15 gallons of foam will run out at around 500 gallons (3 percent of 500 is 15). If flowing foam at a 6 percent concentration, you will run out twice as fast — at around 250 gallons of water.
Another item to note is the foam does not start flowing immediately. It will take about 15-30 seconds before you see the foam start to discharge through the nozzle.
As with anything in the fire service, you need to drill placing a foam operation into action. There are a lot of moving parts involved, but drilling doesn't have to be expensive.
Get some old foam containers or five-gallon paint buckets, fill them with water and put some food dye in the water. This way you can tell whether you are flowing foam. Another option is dish soap in the water to get the foam effect in case you want to practice the roll on, bank or shower methods of application.
The key here is to practice and keep your foam eductor in good operating condition by lubricating the metering valve, cleaning the eductor with mild soap and water, and making sure the metering number settings are well-marked.
This article was written for & published by MultiBriefs.com.