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Protecting Homes from Fire
In communities embedded in the forest, at any given time the local fire department can protect only a small percentage of the homes. In major fires the power is cut off, the residents are evacuated (voluntarily or involuntarily) and the homes are left to burn. Which homes do actually burn is a function of the local peculiarities of wind, topography, fuel, and protective measures taken by the homeowner and the firefighters. [Follow the links below and on the Forest Fire Page for case histories.] Preventative Measures Taken by Prudent Homeowners
Resources to Fight a Major Fire--the Role of Helicopters
Fire-Suppression Module: Versatile Property Protection When the Fire-Suppression Module is flown in to protect a particular property that is not accessible by ground transportation, it brings an array of fire-fighting techniques. Highly variable fire behavior and widely different property configurations require versatility in approach. Direct-Attack on Wildland Fire Near a Property With Adequate Water Supply
The Fire-Suppression Module can pump 100 gallons per minute at 130 psi. It can supply two 1½" fire hoses and a 1" hose simultaneously, provided it is drawing from an adequate water supply. If there is a house to be defended out in the clearing, a second firefighter could create a large wet zone around the house. Thirty feet of suction hose are supplied with the module. A vertical lift of 20' is considered a practical limit for a suction line. For greater distances and greater lifts from a pond, stream, or river, a floating water pump or portable non-floating pump can be used to pump water into a portable storage tank, such as a Fol-Da-Tank®, that holds several thousand gallons. Portable pumps and storage tanks are available as optional items. Foam A small amount of water can be used to generate a large volume of foam. The foam tank and the foam proportioner on the Fire-Suppression Module greatly increase its potential to suppress fire. Laying down a line of foam in front of an advancing fire front, pushing a pile of foam onto a burning hot spot, and covering trees, bushes, and dry grass with foam are effective, time-tested techniques to put out wildfire.
Fire-fighting hand tools--shovel, Pulaski tool (see drawing of wildland firefighter at right), McLeod tool, 5 gallon backpack water tank with hand pump, yellow wildfire hardhat, and first aid kit are items in the toolbox of the Fire-Suppression Module. A trained firefighter uses these tools to quickly put out small spot fires beyond the reach of the hoses before small problems grow to become big problems. Defending a Property Against Wildland Fire Without Additional Water
Long-Term Retardant What can be done to prepare a property to withstand a major wildfire after all personnel are evacuated? One obvious remedy is to protect the property with long-term retardant long before the fire gets this close. Use the Fire-Suppression Module to spray retardant on grass, trees, and all other combustibles, creating a barrier zone around a structure. In contrast to foams and gels, long-term retardant is effective after the water evaporates and remains effective until it is washed away. In the very dry parts of the Western U.S. this means that long-term retardant provides protection for weeks or perhaps a month or so until it rains. If a medium-sized house is surrounded by short grass, the Fire-Suppression Module, fully loaded with 400 gallons of long-term retardant, can treat a zone about 300 feet in diameter. If the house is in a forest with some grass and understory, the zone that can treated with 400 gallons may be reduced to a diameter of about 150 feet or smaller, depending on the density of the vegetation. Large fires that burn for weeks in forested areas with many homes are now an annual occurrence. More than 300 homes burned near Tucson in June, 2003. With helicopter support and one or more Why use a ground crew to spray retardant? Why not just make aerial drops of retardant?
As shown by the fire near Tucson in 2003 and in the Bitterroot Valley of Montana in 2000, fires in forests with very high fuel loads become so large that they cannot be stopped by aircraft dropping retardant. The 2 man crew on the ground can spray retardant on an entire tree trunk and all of the branches, whereas the aerial drop may remain in the canopy high above the ground. The ground crew can spray retardant precisely where it is needed with full coverage. Two colorants are available to mark treated areas. A fugitive colorant fades after a couple of weeks in direct sunlight to a brownish earthen tone. The iron oxide colorant remains bright orangish red until washed away and may stain concrete and light colored painted surfaces. Colorant shows the ground crew what has been protected and what has not; for example, firewood stored under a wooden deck. Colorant informs aircraft monitoring the fire as to which houses have been protected.
Spraying long-term retardant directly on a house greatly increases the protection to keep the house from burning down. However, the retardant works by creating a char layer, which, of course, damages the outside of the house if the fire front moves through the property. Even if the fire does not come to the house, the retardant may damage the paint, requiring significant expense after the fire danger has passed. Long-term retardant provides superior protection, but at a price. A professional ground crew can pay attention to critical details. Embers landing on a roof or being sucked into an attic because air vents were not covered by screen are ways in which otherwise protected houses have burned in previous years.
Short-Term Retardant: Polymer Gel Coating buildings with fire-blocking gel is a "last gap measure" applied almost at the last moment. Under fire conditions typical in the Western United States, with high temperature and extremely low humidity with wind, the polymer gel may only last for 1 or 2 hours before it dries out. However, when the fire front is advancing and is only 1 or 2 ridges away, this window of time can save structures. A well-trained crew can cover a house with a blanket of gel in about 10 to 15
minutes. Handling hose and other items requires some additional time. When operating under
USFS/FAA rules that permit only equipment, but not people, to be transported as an external
load, the Heli-Basket® can be used to bring an All-Terrain Vehicle (ATV, a.k.a. a 4-wheeler), a utility vehicle, or 2 dirt bikes for the fire-protection crew to travel from house to house as the helicopter transports the Fire-Suppression Module and supplies water to sites lacking an available supply. Mop-Up Operations Near a Property If a property survives a major fire, but is surrounded by a "black zone,"
mop-up operations may be required to put out smoldering snag piles and
embers still burning in the duff. The Fire-Suppression Module has a mop-up
wand to reach under the piles of half-burnt logs and debris. Wet foam,
generated by the foam proportioner and foam nozzle, is effective in
smothering "stubborn" hot spots. Who is in the Position to Use PLI's Fire-Suppression Module? The helicopter-transported Fire-Suppression Module is designed for a government agency or large
corporation, which has to defend and protect many properties, or for a fire protection service
company that has contracts with these agencies or corporations. The fire-fighting group most
likely has ground-based vehicles that can protect properties, but previous experience with large
fires has shown the need for getting equipment quickly to the site and the difficulties of created
by narrow roads jammed with traffic or inaccessible locations. Such a fire-fighting group
presumably has the contacts and expertise to integrate a helicopter operation into a
fire-management plan that will be overseen by an Incident Commander. Links to Other Sites Fire Protection Tips for Homeowners Making your home at the Wildland/Urban Interface fire wise from FireWise Home Site Map Products Forest Fire Fire-Fighting Module
Gels Foams Retardant Helicopters Contact Us Orders |
Local Fire Department Can Not Stop a Major Forest Fire
Prudent homeowners living in the wildland/urban interface
reduce the risk of loss though wildfire by constructing their
homes with flame-resistant materials, removing highly
flammable material near their buildings, providing adequate
access to their house and maintaining an emergency water
supply of several thousand gallons. When the fire-boss on a
major fire cruises the neighborhood to decide which
properties can be protected without endangering the lives of
his crew and his equipment, the houses that are quickly
eliminated are those with features such as a long, narrow driveway with no place for a fire truck
to turn around, a wooden deck with firewood stacked underneath, wood shingle roof, wood
siding, evergreen landscaping growing next to house (in particular, juniper and other highly
flammable varieties), pine needles in the rain gutters, dry pine needles and dry dead grass
surrounding the house, and large trees next to the house with large overhanging branches. Such
houses are classified as indefensible. (See links below.)
To defend communities against a major fire, many resources are
mobilized: fire engines, ground crews, and aerial tankers, both fixed wing
and rotary wing. 
The illustration on the left shows some important aspects of fighting forest fire to defend structures. The firefighter is not standing in the forest but rather is standing well back from the flames in the cleared area in front of the forest. He is using a fire hose to deliver water from a large source of water; such as a pond, stream, or river. By wetting down the grass and logs on the ground he will be able to hold the fire line. The fire will burn to the edge of the forest and then stop because it has run out of fuel. The firefighter can quickly extinguish small spot fires that start from embers flying through the air.
Hand Tools
If there is not an adequate supply of water available and if the house is not in a large cleared area, firefighters do not belong in this picture. Too many firefighters have died in high-fuel zones when the wind has changed and the fire has "blown up."