The pros and cons of CAFS

[Guest Homer J.]

I already know the pros of CAFS, so I am not trying to start a debate or re-hash old ideas. I need to know the negative aspects of CAFS, from a scientific (almost maybe) stand point. Forget the usual opinion based nonsense, I need hard facts, figures, DOCUMENTED incidents where CAFS or Class A foam has created problems. Information from the National Institute of Standards and Technology (NIST) is minimal on the subject other than use in fire suppression systems (which works).

I am not looking for the arguements about training, new learning, too complicated or "it will reduce staffing" - so if that is all you have to offer, please don't. Facts Ladies and Gentlemen, thats what I am looking for.

[JM15 386]

I have a question I dont know much about the CAFS can anyone explain a little more about it?

[mfc2257 464]

Millwood Engine 247 - The first (and possibly the only) CAFS engine in Westchester County.

As a former Officer, MPO, and FF that ran often on E-247 out of headquarters I've got a decent amount of experience with CAFS. I've also been involved with several units in the DC/Baltimore/PA metro areas.

IMO the biggest problem is the lack of heat dissapation. CAFS does nothing to help cool the room. Inexperienced or excited FF's quickly extinguish the flames, but the room is just as hot as it was seconds earlier. They proceed deeper into the room to search for more fire OR stand up in the room and encounter deadly temperatures.

Second problem... You cant vent a room with CAFS.... Two reasons... It flows like shaving cream & the nozzles that it is discharged from cannot create a fog like an automatic can.

A minor problem that I've seen a handful of times is when the MPO for whatever reason (runs out of foam, system failure, etc) converts back to straight water while operations are underway, the hoseline goes from being like a garden hose as far as nozzle reaction and weight, to a fully charged line with 100+psi coming from the tip and weighing 8.6lbs/gallon. It will knock a crew on their a** if they aren't prepared for it..... Sometimes it's funny during training, other times at a fire it's dangerous.

I have never seen CAFS used and there be an actual problem with suppression (like it didn't do its job).

CAFS although a wonderful tool for knocking down residential fires that are mostly room and contents, has its limitations. If you are rolling up to a well involved structure, leave the CAFS switch turned off. You are going to have multiple pieces of apparatus besides your CAFS rig that are flowing straight water and you will lose the benefit of CAFS. You will put part of the fire out with CAFS but the area will remain hot enough to reignite as soon as someone washes the CAFS foam off the surface you coated. The best use for a CAFS pumper at a fully involved structure is to protect exposures. There is no substitute for GPM at a fire that cannot be put out from a single CAFS line.

Hope this helps.

JM15..... CAFS stands for Compressed Air Foam System. An over simplified definition of CAFS is Class A foam (which isn't much different than laundry detergent) solution is mixed and then an air compressor will agitate the mixture to create a shaving cream like substance. When you flow this mixture it coats surfaces and seperates with amazing speed the heat, fuel, oxygen mixture that creates fire. So long as the mixture continues to coat the surface of the fuel, it wont burn anymore.

Edited September 29, 2006 by mfc2257

[JM15 386]

thanks for the info mfc2257