Glossary of Terms
Categorical Exclusions are established by the National Environmental Policy Act, and are defined as categories of actions, which do not individually or cumulatively have a signifcant effect on the human environment and therefore noramlly do not require futher analysis in either an environmental assessment or an environmental impact statement.
The leading edge of a relatively cold air mass that displaces warmer air. The heavier cold air may cause some of the warm air to be lifted. If the lifted air contains enough moisture, the result may be cloudiness, precipitation, and thunderstorms. If both air masses are dry, no clouds may form. Following the passage of a cold front in the Northern Hemisphere, westerly or northwesterly winds of 15 to 30 mph or more often continue for 12 to 24 hours.
A method of controlling a partly dead fire edge by carefully inspecting and feeling with the hands for heat to detect any fire, digging out every live spot, and trenching any live edge.
Two or more individual incidents located in the same general area which are assigned to a single incident commander or unified command.
Condition Class 1:
Fire regimes are within a historical range, and the risk of losing key ecosystem components is low. Vegetation attributes (species composition and structure) are intact and functioning within the historical range.
Condition Class 2:
Fire regimes have been moderately altered from their historical range. The risk of losing key ecosystem components is moderate. Fire frequencies have departed from historical frequencies by one or more return intervals (either increased or decreased). This results in moderate changes to one or more of the following: fire size, intensity and severity, and landscape patterns. Vegetation attributes have been moderately altered from their historical range.
Condition Class 3:
Fire regimes have been significantly altered from their historical range. The risk of losing key ecosystem components is high. Fire frequencies have departed from historical frequencies by multiple return intervals. This results in dramatic changes to one or more of the following: fire size, intensity, severity, and landscape patterns. Vegetation attributes have been significantly altered from their historical range.
Contain a Fire:
A fuel break around the fire has been completed. This break may include natural barriers such as a river or road, and/or fireline built by hand, and/or fireline constructed mechanically.
An agency supplying assistance other than direct suppression, rescue, support, or service functions to the incident control effort; e.g., Red Cross, law enforcement agency, telephone company, etc.
A progressive line construction duty using self-sufficient crews who build fireline until the end of the operational period, stay or camp there while off duty, then begin building line again the next operational period where they left off.
The movement of fire through the crowns or tops of trees or shrubs more or less independently of the surface fire. A fire is said to be "crowning" when the flames get up into the tops of trees and spreads.
Drying and browning of herbaceous vegetation or slash.