NWCG Glossary of Wildland Fire, PMS 205

The number of subordinates for which a supervisor is responsible, usually expressed as the ratio of supervisors to individuals. The optimum ratio is five-to-one.

Metal wrench used to tighten and free hose connections.

A device installed in a chimney, flue, or exhaust pipe to stop the emission of sparks and burning fragments.

In WIMS, a group of weather stations.

Officially designated special land types within the fire perimeter.

Aircraft operating in accordance with clearances within control zones in weather conditions less than the basic Visual Flight Rules weather minima.

A further categorization of each General Cause to indicate more specifically the agency or circumstance which started a fire or set the stage for its occurrence.

More specific information about the cause or factors contributing to the ignition.

The heat required to raise a unit mass of a substance one degree kelvin. It is the heat capacity of a system per unit mass; i.e., the ratio of the heat absorbed (or released) to the corresponding temperature rise (or fall).

The smaller area within the general origin area where the fire's direction of spread was first influenced by fuel, weather, and/or topography.

Elapsed time from origin of fire to arrival of the first suppression force.

Standby crew in an area of expected high fire occurrence, generally on a day of critical fire weather.

Retardant drop made from one compartment at a time from an airtanker with a multi-compartment tank.

A divergent wind field. Storms moving into a split field tend to lose strength. Winds are generally light in such a flow field.

Combustion of a thermally isolated material initiated by an internal chemical or biological reaction producing enough heat to cause ignition.

A modified form of broadcast slash burning in which the greater accumulations of slash are fired and the fire is confined to these spots.

The second continuous day of an incident, a regular government employee's normal daily tour of duty is "spot changed" to where the first 8, 9, or 10 hours worked are base hours.

Fire ignited outside the perimeter of the main fire by a firebrand.

A method of lighting prescribed fires where ignition points are set individually at a predetermined spacing and with predetermined timing throughout the area to be burned.

A special forecast issued to fit the time, topography, and weather of a specific incident. These forecasts are issued upon request of the user agency and are more detailed, timely, and specific than zone forecasts. Usually, on-site weather observations or a close, representative observation is required for a forecast to be issued. 

In smokejumping, rappelling, and paracargo operations, the individual responsible for selecting drop target and supervising all aspects of dropping smokejumpers, rappellers, or cargo.

Behavior of a fire producing sparks or embers that are carried by the wind and which start new fires beyond the zone of direct ignition by the main fire.

Water applied through an orifice in finely divided particles to absorb heat and smother fire, to protect exposures from radiated heat, and to carry water toward otherwise inaccessible fire.

A rating of the forward rate of spread of the head of a fire.

A number used to indicate relative (not actual) rate of spread.

Device for combining measured ratings of various fire danger factors into numerical classes or rates of spread.

A small ridge which extends finger-like from a main ridge.

Sudden increase in wind speed to at least 17 mph (15 knots) that is sustained for at least 1 minute but not more than 5 minutes.

Any nonfrontal line or narrow band of active thunderstorms extending across the horizon. It is of importance to fire behavior due to accompanying strong gusty winds and the possibility of such a line passing between regular weather observation stations without being reported.

Condition of the atmosphere in which the temperature decrease with increasing altitude is less than the dry adiabatic lapse rate. In this condition, the atmosphere tends to suppress large-scale vertical motion.

A layer of air having a temperature change (lapse rate) of less than dry adiabatic (approximately -5.4 degrees F per 1,000 feet) thereby retarding either upward or downward mixing of smoke.

Aircraft orbiting the rendezvous area; usually refers to vertical deployment at 500-foot (150 m) altitudinal separation between aircraft.

A case study of a previous incident that is conducted on the actual physical site where the incident occurred. A staff ride is an experiential learning method that involves three distinct parts: a preliminary study, a site visit, and a post-visit integration session. 

A NFDRS component, index or related indicator (ignition component, spread component, energy release component, burning index, Keetch-Byram drought index) whose outputs are correlated to the local fire problem, used to determine staffing levels.

The basis for decision support for daily staffing of initial attack resources and other activities. A level of readiness and an indicator or daily preparedness.

A temporary location for available resources in which personnel, supplies, and equipment await operational assignment.

Atmospheric conditions under which pollutants build up faster than the atmosphere can disperse them.

Fire which kills all or most of the living overstory trees in a forest and initiates forest succession or regrowth. Also explicitly describes the nature of fire in grasslands and some shrublands.

A group of trained firefighters stationed at a dispatch point for quick, rapid deployment.

Fire hose coupling with American National Standard (NH) threads.

Day which produces the same net drying as experienced during a 24-hour period under laboratory conditions in which dry-bulb temperature is maintained at 80º F and relative humidity is maintained at and relative humidity is maintained at 20%.

A two-character code to describe each measurement taken at a weather station.

Specific instructions clearly spelling out what is expected of an individual every time they perform a given task. A standard operating procedure can be used as a performance standard for tasks that are routinely done in the operational environment.

Specific instructions clearly spelling out what is expected of an individual every time they perform a given task. A standard operational procedure can be used as a performance standard for tasks that are routinely done in the operational environment.

Number of acres measured by each Land Owner Kind and Category within a State Code associated with the land within the final fire perimeter of a specific, individual incident. The area measured within the perimeter includes unburned and unburnable islands or portions of such.

A code for the identification of the states, the District of Columbia and the outlying areas of the United States, and associated areas.

Forests owned and administered by a state, and not by a federal government.

A code which expresses the amount of cloud cover, kind of precipitation, and/or restrictions to visibility being observed at the fire danger station at basic observation time.