Act of soaking up and retaining a gas in liquid or in a solid; also retention of radiant energy.

The speed with which a fire moves in a horizontal direction across the landscape, usually expressed in chains per hour or feet per minute.

The relative activity of a fire in extending its horizontal dimensions. It is expressed as rate of increase of the total perimeter of the fire, as rate of forward spread of the fire front, or as rate of increase in area, depending on the intended use of the information. Usually it is expressed in chains or acres per hour for a specific period in the fire's history.

Any wildfire on rangeland.

A constructed building not designed for continuous human occupancy, such as barns, commercial buildings, etc.

A geographical area between two or more jurisdictions into which those agencies would respond on initial attack.

A circular-like flow of a fluid (such as air or water) drawing its energy from a flow of much larger scale, and brought about by pressure irregularities as in the downwind (lee) side of a solid obstacle. For example, wind conditions may be erratic and may eddy on the downwind side of large rock outcroppings, buildings, etc. 

A loose limb, top, or piece of bark lodged in a tree, which may fall on anyone working beneath it.

The rate of heat release per unit time per unit length of fire front. Numerically, it is the product of the heat yield, the quantity of fuel consumed in the fire front, and the rate of spread.

Type of shovel specifically designed for use in constructing a fireline; has a tapered blade with both edges sharpened for scraping, digging, grubbing, cutting, and throwing.