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Glossary of Terms

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- E -

Ecosystem Restoration:
The use and application of the full range of fuel treatments to promote plant community diversity and structure that are more resilient to disturbance, invasive species, and less likely to facilitate uncharacteristically intense wildland fires. Involves restoration of rangelands, short-interval fire-adapted plant communities, and long-interval fire-adapted plant communities.

Energy Release Component (ERC):
The computed total heat released per unit area (British thermal units per square foot) within the fire front at the head of a moving fire.

A ground vehicle providing specified levels of pumping, water, and hose capacity.

Engine Crew:
Firefighters assigned to an engine. The Fireline Handbook defines the minimum crew makeup by engine type.

A situation where personnel are unexpectedly caught in a fire behavior-related, life-threatening situation where planned escape routes or safety zones are absent, inadequate, or compromised. An entrapment may or may not include deployment of a fire shelter. These situations may or may not result in injury; they include "near misses."

Environmental Assessment (EA):
EAs were authorized by the National Environmental Policy Act (NEPA) of 1969. They are analytical documents prepared with public participation to determine whether an Environmental Impact Statement (EIS) is needed for a project or action. If an EA determines an EIS is not needed, the EA becomes the document allowing agency compliance with NEPA requirements.

Environmental Impact Statement (EIS):
EISs were authorized by the National Environmental Policy Act (NEPA) of 1969. Prepared with public participation, they assist decision-makers by providing information, analysis, and an array of action alternatives, allowing managers to see the probable effects of management decisions on the environment. Generally, an EIS is written for a large-scale action or geographical area.

Equilibrium Moisture Content:
Moisture content that a fuel particle will attain if exposed for an infinite period in an environment of specified constant temperature and humidity. When a fuel particle reaches equilibrium moisture content, net exchange of moisture between it and the environment is zero.

Escape Route:
A pre-planned and understood route firefighters can take to move to a safety zone or other low-risk area, such as an already burned area (commonly called "the black"), a previously constructed safety area, a meadow that won't burn, or a natural rocky area that is large enough to provide refuge without being burned.

Extended Attack Incident:
A fire which has exceeded or is expected to exceed initial attack capabilities or prescription.

Extreme Fire Behavior:
"Extreme" implies a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following are usually involved: high rate of spread, prolific crowning and/or spotting, presence of fire whirls, a strong convection column. Predictability is difficult because such fires often exercise influence on their environment and behave erratically, sometimes dangerously.