Firefighters say Gel Works, But Don't Expect Rush to Stockpile It
by Associated Press
TUCSON, Ariz. - Wildland firefighters are generally encouraged at the prospect of another tool to keep houses tucked in forest settings from burning: a sticky goop, or gel, that holds many times its weight in water.
But they don't expect to see an immediate rush among Arizona's municipal fire departments in the so-called urban-wildland interface to stockpile the stuff.
``I think it's a valuable product,'' said Paul Summerfelt, field management officer for the Flagstaff Fire Department. ``It's very effective. There's no question about its effectiveness.''
The gel is an absorbent polymer capable of retaining moisture for several hours, and can be sprayed on structures like homes or cabins from a truck, garden hose, backpack or even from an airplane.
It will adhere to vertical surfaces and - depending on the mix - can have a building-sticking consistency almost like petroleum jelly.
Its effectiveness has been shown on houses and structures in forest fires in such locations as South Dakota's Black Hills National Forest, Colorado's Mesa Verde National Park and in California.
At least a half-dozen gel products approved after testing by the U.S. Forest Service's Missoula Technology and Development Center in Montana are being sold commercially.
Since 2002, wildfires have destroyed more than 800 Arizona homes. The Rodeo-Chediski fire, the largest wildfire in Arizona history, burned 491 homes that year; the Aspen fire the next year destroyed some 320 cabins and homes on Mount Lemmon in southern Arizona, and in 2005, 11 homes were lost in Camp Creek, north of Cave Creek.
Firefighting gel ``has a place in wildland fire protection, but I think also this is a key component: if homeowners did work around their house before the fire, they wouldn't have to use gel or foam or any other products,'' Summerfelt said. ``It may give a false sense of security to property owners that that's all that they have to do.
``If you have to use that on their homes, the appropriate work was not done before the fire'' to clear out vegetation and debris.
``I believe it (gel) probably will be used more in the future,'' said Dugger Hughes, wildland operations specialist with the Northwest Fire District in Tucson.
He said local fire departments also will be able to use additional gel products not yet tested at some point.
Hughes said he has not heard of any municipal fire departments stocking the gels yet, but that ``as they become more tested, as they prove their value, I think we'll start seeing departments stocking the stuff... Most people like myself haven't used it enough to form any opinion.''
``The nice thing about the gels is that they're durable,'' said Shirley Zylstra, a physical scientist and toxicologist at the Missoula center.
The polymers are ``the same thing found in baby diapers,'' she said. ``They have a tremendous amount of ability to hold large amounts of water relative to their weight,'' and they work like a cooling barrier against the building.
``They kind of insulate it against the oncoming fire, Zylstra added.
The gels will remain effective as long as they retain water, which will depend on such factors as heat, humidity, wind and the temperatures created by approaching fire.
They typically can be applied two or more hours ahead of time - longer than foam now in widespread use, which strong winds also are more apt to blow away.
Testing of gels in the Missoula lab began about 8 or 10 years ago for effectiveness and toxicity to people and the environment, Zylstra said.
She said such testing usually takes about two years, and that the market for such products usually is small for a few years after that.
``They've gotten a lot more use in the last three, four, five years,'' Zylstra added.
One drawback: the gel is messy, so cleanup can be difficult, she said.
``The polymers love water, so once the water evaporates, the polymers will pull water from the structure,'' Zylstra said.
Scraping is one solution, though at least one manufacturer has developed a detergent-type formulation, she said.
Anyone can buy the approved products, Zylstra added.
Hughes of the Northwest Fire District said it's likely that homeowners in an urban interface area will invest in gels and equipment to apply them.
``I know people have looked at portable pumps,'' he said. ``Gels probably would work well with them.''
The Forest Service would use gel agents only on federally owned structures, leaving private property to the discretion of municipal fire departments or local homeowners, said Rose Davis, a spokeswoman for the National Interagency Fire Center in Boise, Idaho.
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