In my rural Fire District, we have exactly one hydrant (dry) in a 240-square-mile response area. During the majority of the year, that doesn’t pose a terrible challenge as we are blessed with many ponds, streams, creeks, and the mighty Salmon River to draft water from. Our frozen winters create a whole new ball game as our water sources all freeze over, or freeze to the point where accessing the water in them is beyond hazardous to firefighters and apparatus alike.
Tenders and tankers help, but we all know that these fire apparatus are also limited in their effectiveness by their ability to access water to refill. Also creating a potential challenge is the determination of how badly given fire apparatus leak. (I know—fire engines don’t leak) By the way, if your department has one or more of those trucks that don’t leak but somehow flow water onto the ground when they’re not supposed to, now is the time of year to do what you can to stem those flows.
I’ve heard a number of rural departments considering turning to compressed-air foam systems (CAFS) to help stretch their water. I’m not expressly opposed to CAFS or the use of foam, however, National Fire Protection Association (NFPA) 11, Standard for Low-, Medium-, and High-Expansion Foam, tells us that foam is not suggested or recommended for use on three-dimensional fires, or on things like flowing fuel fires. If you’re going “by the book” and trying to follow NFPA standards, foams are then relegated to horizontal flat-surfaced fires, like airport runways. Foam certainly has its place, but remember what its capabilities are. For those on tighter budgets, also remember that once a jug of protein based foam is opened, it’s shot. My department also has a CAFS, but we’ve found it doesn’t get used enough to retain proficiency, and the time it takes for the volunteers to get it spun up for use is excessive.
While doing research for an article for my other column “To the Rescue,” I learned about rural fire departments batch mixing an encapsulator agent into their apparatus’ tanks and having enormous success with virtually instant knockdown and incredible burn back (rekindle) resistance. These departments tell me that using an encapsulator agent is like having “additional resources and manpower” in a five gallon jug. With this info in mind, I started doing a bit more research. I have used an encapsulator agent since the late 1990s, but my application was almost exclusively confined to major motorsport and super-speedway racing events.
What I learned about today’s encapsulator agents surprised me. Encapsulator agents are not Class A or Class B foam. They are not foam at all. Although listed in NFPA 18A, Standard on Water Additives for Fire Control and Vapor Mitigation, in the class of wetting agent, there is verbiage and specific criteria and field tests within the standard that separate encapsulator agents from wetting agents and foams. Albeit really interesting, there isn’t enough room in this column to explain the science and chemistry that explains how encapsulator agents work. I can tell you that fire department apparatus in Germany and throughout other parts of Europe have been required to use encapsulator agent for some time now and do so with fantastic success. I will follow this article up with other state of the art applications for this technology, but for now, let’s get back to some benefits of using encapsulator in rural fire apparatus.
One of the big questions that I had about encapsulator use is what temperature it freezes at, and does freezing and thawing change its effectiveness? The answer I was given by a manufacturer of a popular encapsulator agent is as follows: Water freezes at 32°F. Its encapsulator agent freezes at 17°F. There is no chemical change in their encapsulator agent after freezing and thawing repeatedly. As a matter of fact, this manufacturer showed me that it has a repeated freeze/thaw test as part of its quality control and quality assurance programs. This particular UL-listed product is biodegradable, nontoxic, and noncorrosive. Unlike traditional foam, it is not considered a hazardous material in either its concentrated form or once in solution.
Because of encapsulator agents’ instant cooling (autoignition temperature reduction) and quick knockdown ability through hydrocarbon and vapor encapsulation, manufacturers boast the ability to reduce firefighting water usage by 50 percent or more.
The independent testing I have done with my encapsulator agent of choice is nothing short of mind blowing, and I can personally attest to the validity of manufacturer’s claims as they pertain to the testing I’ve done so far. I’m sold on the technology, but I strongly encourage you to find an encapsulator agent and do testing and research of your own to see if it works for you. I think you will be pleasantly surprised.
The encapsulator agent I am testing is priced at about the same price as traditional foams and is considerably less expensive than AR-AFFF. One of the reasons for this is that foams are traditionally used at 3 or 6 percent in educted solutions. Encapsulator agents are mostly used in a 1 or 3 percent solution, which often allows them to be more cost-effective, and encapsulator agents do not require special nozzles or eductors for use because there is no foam blanket to form. Encapsulator agent can also be batch mixed inside the apparatus tank (provided the solution can stay in the tank and not leak out onto the station floor).
I offer this information on encapsulator agents as another tool for your firefighting toolbox and as a possible solution for frigid winter (and year round) firefighting when you have to haul water to your fires.
CARL J. HADDON is a member of the Fire Apparatus & Emergency Equipment editorial advisory board and the director of Five Star Fire Training LLC, which is sponsored, in part, by Volvo North America. He served as assistant chief and fire commissioner for the North Fork (ID) Fire Department and is a career veteran of more than 25 years in the fire and EMS services in southern California. He is a certified Level 2 fire instructor and an ISFSI member and teaches Five Star Auto Extrication and NFPA 610 classes across the country.