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Appendix A, Fire Readiness plan, May 2004 CHAPTER APPENDIX A ATTACHMENT #1 RELATIONSHIP BETWEEN FIRE DANGERAND EXPECTED FIRE BEHAVIOR L LOW: Fuels do not ignite readily from small firebrands, .although a more intense .heat source, such -as lightning, may start many fires, in duff or punky .wood. Fire in open-cured grass may burn freely a few hours after rain, but woods fires. spread slowly byoreeping or smoldering, and bum in irregular fingers. There is little danger of spotting. Control and mop-up should he easy. II. MODERATE: Fires can start from most accidental causes, but with the exception of lightning fires in some areas, the number of.starts is generally low. Fires in open-cured grass will burn briskly and spread rapidly on windy days. Woods fires spread slowly to moderately fast. The average fire is of moderate intensity, although heavy concentrations of fuel; especially draped .fuel, may bum hot. ` Short-distance spotting may occur, but is not persistent. Fires are not likely to become serious, and control is relatively easy. . �. HIGH: All fine dead fuels ignite readily , and fires start easily from most causes. Unattended debris burning is likely to escape. Fires spread rapidly and short-distance spotting is common. High intensity burning may develop in concentrations of fuel. Fires may become serious and their control difficult, unless they are hit hard and fast while small. Caution on mop-up is required. IV. VERY HIGH: Fires start easily from all :causes, and immediately after ignition spread rapidly and increases quickly in intensity. Spot fires are a constant danger. When fires buming in . light .fuels move into heavier fuels, they may quickly develop high-intensity characteristics such as long-distance spotting and fire whirlwinds. Direct attack at the head of such fires is rarely possible after they have been burning more than a few minutes. -Fires burning into swamps or muck will be a control problem. Special attention is required on mop-up- V. EXTREME: Fires start quickly„ spread furiously, and burn intensely. All fines are potentially serious. Development into high-intensity burning will usually be faster and occur from smaller fires than in the very high danger class. Direct attack is rarely possible, and may be dangerous, except immediately after ignition. Fires that develop headway in heavy slash or in pine stands may be unmanageable while the extreme burning condition lasts. Under-these conditions, the only effective and safe contrml-action is_on .the flanks..until_the weather changes or the fuel supply lessens. Fires in swamps and muck present unusually difficult control problems. Very intense efforts are necessary for effective mop-up.