Aerial photographs corrected to scale such that geographic measurements may be taken directly from prints. They may contain graphically emphasized geographic features and may be provided with overlays of such features as: water systems, facility location, etc. 

Photograph obtained from the orthogonal (i.e., horizontal) projection of a correctly oriented stereoscopic model formed by two overlapping aerial photographs; an orthophoto is free of tilt and relief displacements.

The two-category (evergreen, deciduous) classification of shrubs vegetation in the 1988 version of NFDRS.

Material (usually a flammable liquid) used to initiate or increase the spread of a fire.

Chipping or pitting of concrete, masonry, or stone surfaces.

A hose lay consisting of consecutively coupled lengths of hose without laterals. The lay is extended by inserting additional lengths of hose in the line between pumps and nozzle.

A principal low cloud type in the form of individual cauliflower-like cells of sharp non-fibrous outline and less vertical development than cumulonimbus.

The composition of air with respect to quantities of pollution therein; used most frequently in connection with "standards" of maximum acceptable pollutant concentrations. Used instead of "air pollution" when referring to programs.

The spread of the fire from one location to another.

Single round trip made by an airtanker from a tanker base to a fire and return.