A fire resulting from any operation or activity of a railroad, except smoking.

Identifiable human activity that historically has been a major cause of wildfires on a protection unit; one of the eight general causes listed on the standard fire report.

A control mechanism that allows a regulated quantity of foam concentrate to be introduced into the main hose line.

The vertical measurement of vegetation from the top of the crown to ground level.

An estimate of the potential difficulty of fire containment as it relates to the flame length at the head of the fire.

Different areas of the fire usually determined by the predominant direction of fire spread and delineated from the fastest moving area (head) to the slowest moving area (base or tail). The most rapidly moving portion is designated the head of the fire, the adjoining portions of the perimeter at right angles to the head are known as the flanks, and the slowest moving portion is known as the rear or the base of the fire. 

The most rapidly spreading portions of a fire’s perimeter, usually progressing with the wind, up slope, or a combination of the two.

That portion of a fire edge opposite the head.

That portion of a fire backing directly away from and in relatively close proximity to the ignition area. The slowest spreading portion of a fire edge and generally opposite the head.

The use of fire to accomplish a specified objective.