NWCG Glossary of Wildland Fire, PMS 205

Any steel tracked vehicle equipped with a front mounted blade used for exposing mineral soil.

A resource that includes a dozer, its transportation unit and a standard complement of personnel for its operation.

Fireline constructed by the front blade of a dozer.

Any ground vehicle with personnel capable of maintenance, minor repairs, and limited fueling of dozers.

Drawing water from static sources such as a lake, pond, cistern, river, etc. into a pump which is above the level of the water supply. This is done by removing the air from the pump and allowing atmospheric pressure [14.7 psi (101 kPa) at sea level] to push water through a noncollapsible suction hose into the pump. 

The time (minutes) it takes for foam solution to drop out from the foam mass; for a specified percent of the total solution contained in the foam to revert to liquid and drain out of the bubble structure.

Needles, leaves, and twigs that have fallen from above and have lodged on lower branches or brush. Draped fuels are part of aerial fuels.

Effect of wind on smoke, retardant drops, paracargo, smokejumper streamers, etc.

Smoke that has drifted from its point of origin and is no longer dominated by convective motion. May give false impression of a fire in the general area where the smoke has drifted.

Hand-held device for igniting fires by dripping flaming liquid fuel on the materials to be burned; consists of a fuel fount, burner arm, and igniter. Fuel used is generally a mixture of diesel and gasoline.

An axle that supports a portion of the vehicle weight and transmits a driving force to the wheels.

Wheels powered by all of the vehicle's drive axles. Dual tires are considered as single wheels. The number of wheels is commonly referenced by the terms "4x2", "4x4", etc. where the first figure indicates the total number of wheels on the ground and the second figure, the number of drive wheels.

Precipitation composed exclusively of water drops smaller than 0.02 inches (0.5 mm) in diameter.

The type of retardant drop selected to cover a ground target. Terms that can specify the type of drop configuration include Salvo Drop and Trail Drop.

Indicates that the airtanker has the target in sight and will make a retardant drop on this run over the target.

The distribution of an aerially delivered retardant drop on the target area in terms of its length, width, and momentum (velocity x mass) as it approaches the ground. The latter determines the relative coverage level of the fire retardant on fuels within the pattern. 

Target area for airtankers, helitankers, cargo dropping.

A period of relatively long duration with substantially below-normal precipitation, usually occurring over a large area.

A number representing the net effect of evaporation, transpiration and precipitation in producing cumulative moisture depletion in deep duff or upper soil layers.

Device used to transport a 55-gallon drum (208 L) via sling on a helicopter.

The government furnishes all operating supplies after the equipment arrives at the incident.

The rate of decrease of temperature with height of a parcel of dry air lifted adiabatically through an atmosphere in hydrostatic equilibrium. Numerically equal to 9.7670 C degrees per km or about 5.40 F degrees per thousand feet.

A portion of the atmosphere that has a relatively low dew point temperature and where the formation of clouds, fog, or precipitation is unlikely.

A name given to an ordinary thermometer used to determine the temperature of the air (to distinguish it from the wet bulb).

A contiguous series of days having a pre-established number of fire ignitions with a fuel dryness level that historically resulted in a significant fire event for a particular area.

A low expansion foam type with stable bubble structure and slow drain time which is used primarily for resource and property protection.

Permanent devices with fire engine threads attached to expedite drafting operations in locations where there are water sources suitable for use in fire suppression (e.g., piers, wharves, bridges over streams, highways adjacent to ponds).

Permanently installed supply private fire pumps which depend upon suction sources.

Thunderstorm in which negligible precipitation reaches the ground.

A trial pass over the target area by a leadplane and/or an airtanker to pinpoint target areas and warn ground personnel of the impending retardant or extinguishing agent drop.

Refers to dry chemical retardants stored at air attack bases and available for mixing with water.

The temperature of the air measured in the shade 4-8 feet above the ground.

In a psychrometer, the thermometer not covered with muslin which is used to determine air temperature.

The layer of decomposing organic materials lying below the litter layer of freshly fallen twigs, needles, and leaves and immediately above the mineral soil.

The effective life span of foam bubbles.

Regular number of hours worked per week by a full-time firefighter, excluding overtime.

A circular-like flow of a fluid (such as air or water) drawing its energy from a flow of much larger scale, and brought about by pressure irregularities as in the downwind (lee) side of a solid obstacle. For example, wind conditions may be erratic and may eddy on the downwind side of large rock outcroppings, buildings, etc. 

The boundary between two fairly distinct fuel types.

The place where plant communities meet or where successional stages or vegetative conditions within plant communities come together.

Method of burning in which fires are set along the edges of an area and allowed to spread inward.

Name of the person editing the feature.

A device used to introduce and mix fire chemical into a water stream. An eductor is a fitting with three ports, an inlet for water flow, an outlet for water flow, and an inlet for fire chemical concentrate. The flow of water through the eductor produces a region of lower pressure at the fire chemical inlet, drawing the chemical into the water stream. 

The midflame wind speed adjusted for the effect of slope on fire spread.

A siphon device used to fill an engine's tank when the water source is below or beyond the engine's drafting capability.

The total time taken to complete any step(s) in fire suppression.

Conceptually represents the optimum integration of modern educational methods and professional staff development training with state of the art technology. The primary goal is enhancing on-the-job performance, motivation, and learning performance.

In hydraulics, the pressure loss caused by raising water through hose or pipe to a higher elevation (roughly equal to one psi for every two-foot increase in elevation above the pump) (11.3 kPa per meter).

Any incident, whether natural, technological, biological, or human-caused, that necessitates responsive action to protect life or property.