A cache may consist of a number of portable radios, base station, and, in some caches, a radio repeater that is stored in a predetermined location for dispatch to incidents.

Lopping logging debris and spreading it more or less evenly over the ground.

Progressive method of fireline construction on a wildfire without changing relative positions in the line. Work is begun with a suitable space between workers; whenever one worker overtakes another, all of those ahead move one space forward and resume work on the uncompleted part of the line. The last worker does not move ahead until work is completed in his/her space. Forward progress of the crew is coordinated by a crew boss. 

An organized group of firefighters under the leadership of a crew boss or other designated official.

Any natural catastrophe or, regardless of cause, any fire, flood, or explosion, in any part of the United States, which in the determination of the President causes damage of sufficient severity and magnitude to warrant major disaster assistance.

The natural resources of an area, such as timber, grass, watershed values, recreation values, and wildlife habitat.

Small particles of carbon, tarry and water vapor resulting from the incomplete combustion of carbonaceous materials such as wood, coal or oil.

Visibility impairment caused by the cumulative air pollutant emissions from numerous sources over a wide geographic area.

A sufficient concentration of atmospheric aerosols to affect a visible attenuation of light and measurable reduction in visual range. The aerosol particle diameter is near the wavelength of visible light, optimizing the light scattering efficiency of the particles. 

Method of upper-air observation consisting of an evaluation of the wind speed and wind direction, temperature, pressure, and relative humidity aloft by means of a balloon-borne radiosonde tracked by a radar or radio direction-finder.