A continuous, five-step process that provides a systematic method for identifying and managing the risks associated with any operation.

A plan developed by the Structure Protection Specialist that provides operational guidelines to suppression resources responsible for providing wildland fire structure protection.

Passage of liquid through a porous body, as movement of water through soil.

Fireline that has been controlled. The fire has been mopped up for a safe distance inside the line and can be considered safe to leave unattended.

Contribution of a specific source to human-caused risk, derived from the daily activity level assigned a risk source and its risk source ratio.

Spacing of aircraft while landing and taking off at airports to achieve safe and orderly movement in flight.

Wildfire caused directly or indirectly by lightning.

Fire caused by mechanical equipment other than railroad operations.

Foam intended for use on Class A or woody fuels; made from hydrocarbon-based surfactant, therefore lacking the strong filming properties of Class B foam, but possessing excellent wetting properties.

Spinning vortex column of ascending hot air and gases rising from a fire and carrying aloft smoke, debris, and flame. Fire whirls range in size from less than one foot to over 500 feet in diameter. Large fire whirls have the intensity of a small tornado.