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Glossary of Terms

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- H -

Haines Index:
An atmospheric index used to indicate the potential for wildfire growth by measuring the stability and dryness of the air over a fire.

Hand Line:
A fireline built with hand tools, such as shovels and pulaskis.

Hazard Fuel Reduction:
Removal of excessive live or dead wildland fuel accumulations for the strict objective of reducing the potential for the occurrence of uncharacteristically intense wildland fire and increasing capabilities to protect life and property, including communities at risk and sensitive municipal watersheds; sensitive natural resources, including critical native plant communities and threatened and endangered species; and other socially important cultural resources.

Hazard Reduction:
Any treatment of a hazard that reduces the threat of ignition and fire intensity or rate of spread.

Head of a Fire:
The portion of the fire having the fastest rate of spread.

Heavy Fuels:
Fuels of large diameter such as snags, logs, and large limb wood, that ignite and are consumed more slowly than flashy fuels.

The main location within the general incident area for parking, fueling, maintaining, and loading helicopters. The helibase is usually located at or near the incident base.

A temporary landing spot for helicopters.

The use of helicopters to transport crews, equipment, and fire retardant or suppressant to the fireline during the initial stages of a fire. Helitack can also refer to personnel, as in helitack crews.

Helitack Crew:
A group of firefighters trained in the technical and logistical use of helicopters for fire suppression.

Holding Actions:
Planned actions required to achieve wildland prescribed fire management objectives. These actions have specific implementation timeframes for fire use actions but can have less sensitive implementation demands for suppression actions.

Holding Resources:
Firefighting personnel and equipment assigned to do all required fire suppression work following fireline construction but generally not including extensive mop-up.

Hose Lay:
Arrangement of connected lengths of fire hose and accessories on the ground, beginning at the first pumping unit and ending at the point of water delivery.

Hotshot Crew:
A highly trained and experienced fire crew used mainly to build fireline by hand. Hotshots -- also called Interagency Hotshot Crews or IHCs -- are national resources, also called Type 1 crews.

A particular active part of a fire.

Reducing or stopping the spread of fire at points of particularly rapid rate of spread or special threat, generally the first step in prompt control, with emphasis on first priorities.