The top layer of forest floor, composed of loose debris of dead sticks, branches, twigs, and recently fallen leaves or needles; little altered in structure by decomposition.

Layer of decomposed organic matter on the forest floor beneath the fermentation layer and directly above the soil. It is that part of the duff in which decomposition has rendered vegetation unrecognizable and mixing of soil and organic matter is underway.

Two or more firefighters stationed at a strategic location for initial action on fires. Duties are essentially the same as those of individual firefighters.

Readily vaporized organic materials which, when mixed with oxygen, are easily ignited.

A title for subordinates of principal Command Staff and EOC director’s staff positions. The title indicates a level of technical capability, qualification, and responsibility subordinate to the primary positions. Assistants may also be assigned to unit leaders.

A neoprene tank designed for attachment to the landing skid frame of a helicopter. It has a capacity of 80 to 100 gallons (303 to 378 liters) of water or retardant.

The relative ease with which fuels ignite and burn regardless of the quantity of the fuels. Preferred to "inflammability."

Something that represents, promotes or enhances a desired outcome, being of positive value and contributing to the attainment of organizational goals. Benefits represent one end of the spectrum of outcomes from fire, with the opposite end being harm, loss or damage. 

Fire effects with positive monetary, social, or emotional value or that contribute, through changes in the resource base, to the attainment of organizational goals.

The distance from the centerline of the front axle to the centerline of the rear axle. For a tandem rear axle vehicle the center line is midpoint between the centers of the two rear axles.