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[The definitions for terms that appear in italics in this glossary were obtained from the Glossary of Wildland Fire Terminology (NFES 1832), National Wildfire Coordinating Group, 1996].

accountability tags:
Identification cards that are collected at an incident and returned at conclusion to ensure no one is left behind.

aerial fuels:
Standing and supported live and dead combustibles not in direct contact with the ground and consisting mainly of foliage, twigs, branches, stems, cones, bark, and vines.

A term used in fire protection assessment planning that refers to the combining of information gathered for an area concerning hazards, risks and values related to fire potential, which is then used to develop fire management units.

allowable burned area:
Maximum average area burned over a specified period of years that is considered an acceptable loss for a specified area under organized fire suppression.

anchor point:
An advantageous location, usually a barrier to fire spread from which to start constructing a fireline. Used to minimize the chance of being flanked by the fire while the line is being constructed.

available fuel:
The portion of the total fuel that actually burns under various environmental conditions.

Used in some localities to specify a fire set to spread against the wind in prescribed burning.

A tactic associated with indirect attack, intentionally setting fire to fuels inside the control line to slow, knock down, or contain a rapidly spreading fire. Backfire provides a wide defense perimeter and may be further employed to change the force of the convection column. Backing fire makes possible a strategy of locating control lines at places where the fire can be fought on the firefighter's terms. Except for rare circumstance meeting specified criteria, backing fire is executed on a command decision made through line channels of authority.

bambi bucket:
A collapsible bucket slung below a helicopter. Used to dip water from a variety of sources for fire suppression.

Any obstruction to the spread of fire. Typically, an area or strip devoid of flammable fuel.

Ridge of soil or debris that is along, outside, or on the downhill side of a ditch or trench, resulting from line construction.

Sudden increase in fire intensity or rate of spread sufficient to preclude direct control or to upset existing control plans. Often accompanied by violent convection and may have other characteristics of a fire storm.

brand patrol: (Local terminology)
Person or persons assigned to look for and extinguish spot fires.

A fire edge that crosses a control line or natural barrier intended to confine the fire. The resultant fire. Also called slopover.

broadcast burning:
Intentional burning in which fire is intended to spread over all of a specific area within well defined boundaries.

A collective term that refers to stands of vegetation dominated by shrubby, woody plants, or low growing trees, usually of a type undesirable for livestock or timber management.

brush fire:
Local terminology for wildfire. See wildfire.

brush truck:
An all wheel drive protectively armored engine with pump and roll capability which is able to maneuver through various wildland fuels in a direct attack fire suppression mode.

1. Cumulative effects of drying (during a preceding period) on the current fire danger.
2. Acceleration of a fire with time.
3. Increase in strength of a fire management organization.

burning conditions:
The state of the combined factors of environment that affect fire behavior in a specific fuel type.

burning index:
An estimate of the potential difficulty of fire containment as it relates to the flame length at the head of the fire. A relative number related to the contribution that fire behavior makes to the amount or effort needed to contain a fire in a particular fuel type within a rating area.

burning-index meter:
A device used to determine burning index for different combinations of burning index factors.

burning period:
That part of each 24 hour period when fires will spread most rapidly. Typically, this is from 10 a.m. to sundown.

burn out:
Setting fire inside a control line to consume fuel between the edge of the fire and the control line.

Central Pine Barrens:
A statutorily defined 100,000 acre, geographic area as per New York State Environmental Conservation Law Section 57-107.10, that is located within the central and eastern portions of Suffolk County in New York. This area includes parts of the Towns of Brookhaven, Riverhead and Southampton and is divided into two regions: an approximately 52,500 acre Core Preservation Area and an approximately 47,500 acre Compatible Growth Area that surrounds the core area. A comprehensive land use management plan was prepared in 1995 that regulates development in this area in order to preserve and protect its ecological and hydrological resources.

check line:
A temporary line constructed at right angles to the control line, and used to hold a backing fire in check as a means of regulating the heat (or intensity) of the backfire.

class of fire (as to kind of fire for purpose of using proper extinguisher):
Class A: Fire in solid fuels, including forest fires.
Class B: Fire in flammable liquids.
Class C: Fire in electrical equipment.
Class D: Fire involving certain combustible metals.

closed area:
An area in which specified activities or entry are temporarily restricted to reduce risk of person-caused fires.

cold trailing:
A method of controlling a partly dead fire edge by carefully inspecting and feeling with the hand to detect any fire, digging out every live spot, and trenching any live edge.

command post:
The location from which all fire operations are directed. There is normally only one command post for each fire situation.

command staff:
The command staff consists of the information officer, safety officer, and liaison officer. They report directly to the incident commander and may have an assistant or assistants, as needed.

Compatible Growth Area:
The area within the Central Pine Barrens, but outside of the core preservation area as defined in New York State Environmental Conservation Law Section 57-0107.12.

condition of vegetation:
Stage of growth, or degree of flammability, of vegetation that forms part of a fuel complex. Herbaceous stage is at times used when referring to herbaceous vegetation alone. In grass areas minimum qualitative distinctions for stages of annual growth are usually green, curing, and dry or cured.

confine a fire:
The least aggressive wildfire suppression strategy, typically allowing the wildland fire to burn itself out within restrict determined natural or existing boundaries such as rocky ridges, streams and possibly roads.

contain a fire:
A moderate aggressive suppression strategy, which can reasonably be expected to keep the fire within established boundaries of constructed firelines under prevailing conditions.

control a fire:
To complete a control line around a fire, any spot fires therefrom, and any interior islands to be saved; burnout any unburned area adjacent to the fire side of the control lines; and cool down all hotspots that are immediate threats to the control line, until the lines can reasonably be expected to hold under foreseeable conditions.

control force:
Personnel and equipment used to control a fire.

control line:
An inclusive term for all constructed or natural fire barriers and treated fire edge used to control a fire.

Core Preservation Area:
The area of the Central Pine Barrens that comprises the largest intact areas of undeveloped pine barrens as defined in New York State Environmental Conservation Law Section 57-0107.11.

crew boss:
A person in supervisory charge of usually 16 to 21 firefighters and responsible for their performance, safety, and welfare.

crown fire:
A fire that advances from top to top of trees or shrubs more or less independently of the surface fire. Sometimes crown fires are classed as either running or dependent, to distinguish the degree of independence from the surface fire.

defensible space:
Refers to distances from exposures to wildfire hazards in relation to the ability to safely protect those exposures.

The act or system of discovering and locating fires.

Local terminology used to describe initial suppression activity where equipment is working on the head of the fire.

direct attack:
Any treatment applied directly to burning fuel, e.g., by wetting, smothering, or chemically quenching the fire or by physically separating the burning from unburned fuel.

Local terminology to describe initial suppression activity where equipment is working on the sides of the fire where intensity is lower.

Determination that a fire exists. In contrast to detection, location of a fire is not required.

A person who receives reports of discovery and status of fires, confirms their location, takes action promptly to provide people and equipment likely to be needed for control efforts.

A unit established to divide an incident into geographical areas of operation.

drought index:
A number representing net effect of evapotranspiration and precipitation in producing cumulative moisture-depletion in deep duff or upper soil layers.

The partly decomposed organic material of the forest floor beneath the litter of freshly fallen twigs, needles, and leaves.

elapsed time:
Total time taken to complete any given step(s) in fire suppression.

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

equipment use fire:
Fire caused by mechanical equipment other than railroad operations.

escape route:
A pre-planned and understood route firefighters take to move to a safety zone or other low-risk area. When escape routes deviate from a defined physical path, they should be clearly marked (flagged).

escaped fire:
A fire which has exceeded or expected to exceed initial attack capabilities or prescription.

Escaped Fire Situation Analysis (EFSA):
A decision analysis that uses factors that influence suppression of an escaped fire from which a plan of action will be developed. The analysis includes the development of alternative suppression strategies and the probable cost and damages associated with each.

1. Property that may be endangered by a fire burning in another structure or by a wildfire.
2. Direction in which a slope faces, usually with respect to cardinal directions.
3. The general surroundings of a site with special reference to its openness to winds.

exposure fire:
Classification for a fire not originating in a building, but which ignites building(s). A fire originating in one building and spreading to another is classified under the original cause of fire.

extended attack incident:
A wildland fire that has not been contained or controlled by initial attack forces and for which more firefighting resources are arriving, en route, or being ordered by the initial attack incident commander. Extended attack implies that the complexity level of the incident will increase beyond the capabilities of initial attack incident command.

fine fuel moisture:
The probable moisture content of fast-drying fuels which have a time lag constant of one hour or less; such as, grass, leaves, ferns, tree moss, draped pine needles, and small twigs (0-1/4").

fire analysis:
Process of reviewing the fire control action on a given unit or the specific action taken on a given fire in order to identify reasons for both good and poor results, and to recommend or prescribe ways and means of doing a more effective and efficient job.

fire behavior:
The manner in which a fire reacts to the variables of fuel, weather, and topography.

A natural or constructed barrier used to stop or check fires that may occur or to provide a control line from which to work.

fire chief:
Individual elected by the members of the fire department of the fire district whose duties are defined under the Consolidated Laws of New York Annotated Town Law, Chapter 62, Article 11-- Fire, Fire Alarm and Fire Protection Districts, Section 176-a. The chief under the direction of the board of fire commissioners has exclusive control of the members of the fire department of the fire district at all fires, inspections, reviews and other occasions when the fire department is on duty or parade. He also has supervision of engines, fire trucks, and other firefighting apparatus and property used for the prevention or extinguishment of fire and of all officers and employees of the fire department and ensures the rules and regulations of the board of commissioners are observed and duly executed.

fire classification:
Numerical category 1 to 7 that indicates the severity of a fire with 1 representing the lightest and 7 representing a conflagration of 5,000 acres or more.

fire commissioners:
Individuals appointed by the town board, to serve on a board of fire commissioners that is comprised of five fire district commissioners and a treasurer that serve without compensation, except for the secretary whom may be compensated. According to Consolidated Laws of New York Annotated Town Law, Chapter 62, Article 11-- Fire, Fire Alarm and Fire Protection Districts, Section 176, the board has the authority to organize, operate, maintain and equip fire companies and may adopt rules and regulations governing all fire companies and fire departments in said district and prescribe the duties of the members. Such rules and regulations shall not interfere with the duties of the chief or assistant chief at such times as the fire department or any company or squad thereof is on duty.

fire control:
All activities to protect wildland from fire. (Includes prevention, pre-suppression, and suppression.)

fire control equipment:
All tools, machinery, special devices, and vehicles used in fire control, but excluding structures.

fire damage:
Detrimental fire effects expressed in monetary or other units including the unfavorable effects of fire changes in the resource base on the attainment of organizational goals.

fire danger:
Sum of constant danger and variable danger factors, affecting the inception, spread, and resistance to control, and subsequent fire damage, often expressed as an index.

Fire Danger Rating System:
A system used to estimate the potential for forest fires based on weather factors and vegetation condition.

fire danger station:
A specific location where certain basic weather elements affecting fire are measured.

fire department:
An organization for preventing or extinguishing fires.

fire district:
As defined in Consolidated Laws of New York Annotated Town Law, Chapter 62, Article 11-- Fire, Fire Alarm and Fire Protection Districts, Section 174.7, a fire district is a political subdivision of the state and a district corporation within the meaning of section three of the general corporation law. The officers and employees of a fire district, including the paid and volunteer members of the fire department are officers and employees of such fire district and are not officers or employees of any other political subdivision.

fire effects:
The physical, biological, and ecological impact of fire on the environment.

Person whose principal function is fire suppression.

The part of a control line that is scraped or dug to mineral soil. Also called fire trail.

fire management:
Activities required for the protection of burnable woodland values from fire, and the use of prescribed fire to meet land management goals and objectives.

fire management analysis zone (FMAZ):
The basic geographical (analysis) area represented by a single set of fire behavior characteristics based on fuels, topography, and local weather.

Fire Protection Assessment (FPA) planning;
A tool used by fire managers, resource managers and other stakeholders to make quality resource management decisions concerning fire management for a specific area. It involves identifying the hazards, risks, values as they relate to fire potential, which are used to develop fire management zones. The final product of a fire protection assessment is a fire management action plan that identifies fire suppression tactics and strategies, fire prevention actions, and fuel management priorities needed for this area.

fire protection district:
A fire district that contracts with a fire district, fire department or fire company outside of that district for fire protection services.

fire resistive:
Material that is covered in a substance that increases its ignition point, thereby reducing the probability of burning.

fire scar:
1. A healing or healed injury or wound to woody vegetation, caused or accentuated by a fire.
2. The mark left on a landscape by fire.

fire season:
The period or periods of the year during which fires are likely to occur, spread, and do sufficient damage to warrant organized fire control.

fire storm:
Violent convection caused by a large continuous area of intense fire. Often characterized by destructively violent surface indrafts near and beyond the perimeter, and sometimes by tornado-like whirls.

fire weather forecast:
A weather prediction specially prepared for use in wildland fire operations and prescribed fire.

fire weather index:
A numerical rating based on meteorological measurement of fire intensity in a standard fuel. Fire weather index is comprised of three fuel moisture codes, covering classes of forest fuels of different drying rates and two indices that represent rate of spread and amount of available fuel.

fire weather station:
A forest meteorological station specially equipped to measure weather elements that have an important effect on fire behavior.

The relative ease with which fuels ignite and burn regardless of the quantity of the fuels. Preferred to "inflammability."

flanking fire suppression:
Attacking a fire by working along the flanks either simultaneously or successively from a less active or anchor point and endeavoring to connect the two lines at the head.

Any sudden acceleration of fire spread or intensification of the fire. Unlike blowup, a flare-up is of relatively short duration and does not radically change existing control plans.

flash fuels:
Fuels such as grass, leaves, draped pine needles, fern, tree moss, and some kinds of slash which ignite readily and are consumed rapidly when dry.

A chemical fire extinguishing mixture. When applied it forms bubbles which greatly increase the mixture volume. It adheres to the fuel, and reduces combustion by cooling and moistening and by excluding oxygen.

forest fire:
A wildland fire not prescribed for the area by an authorized plan.

A natural or manmade change in fuel characteristics which affects fire behavior so that fires burning into them can be more readily controlled.

fuel characteristics:
Factors that make up fuels such as compactness, loading, horizontal continuity, vertical arrangement, chemical content, size and shape, and moisture content.

fuel ladders:
Fuels above ground and their vertical continuity, which influences fire reaching various levels or vegetation strata. (Also called vertical fuel arrangement).

fuel models:
Mathematical models that have been developed to quantitatively rate fire danger and predict fire behavior. The models require descriptions of fuel properties as inputs to calculations of fire danger indices of fire behavior potential. The collections of fuel properties have become known as fuel models.

fuel moisture content:
The quantity of moisture in fuel expressed as a percentage of the weight when thoroughly dried at 212 F.

fuel-moisture indicator stick:
A specially prepared stick or set of sticks of known dry weight continuously exposed to the weather and periodically weighed to determine changes in moisture content as an indication of moisture changes in wildland fuels.

fuel reduction:
Manipulation, including combustion, or removal of fuels to reduce the likelihood of ignition and/or to lessen potential damage and resistance to control.

fuel type:
An identifiable association of fuel elements of distinctive species, form, size, arrangement, or other characteristics that will cause a predictable rate of spread or resistance of control under specified weather conditions.

global positioning system:
A satellite navigation system used for military and civilian applications, funded and controlled by the U.S. Department of Defense, that is used for navigation in three dimensions, precise positioning, time and frequency dissemination and other research.

ground fire:
Fire that consumes the organic material beneath the surface litter of the forest floor, such as, peat fire.

hand crews;
Personnel assigned to a given fire that use hand tools to suppress or mop-up the fire with fire lines.

A fuel complex defined by kind, arrangement, volume, condition, and location that forms a special threat of ignition and resistance to control.

hazard reduction:
Any treatment of living and dead fuels that reduces the threat of ignition and spread of fire.

As used in fire protection assessment planning, they are management units based on the physical or biological features resulting in similar fire behavior characteristics that are ranked as high, moderate or low depending on their potential for extreme fire behavior and their resistance to control.

head fire:
A fire spreading or set to spread with the wind.

head of fire:
The most rapidly spreading portion of a fire's perimeter, usually to the leeward or up slope.

heavy fuels:
Fuels of large diameter such as snags, logs, and large limbwood, which ignite and are consumed more slowly than flash fuels. Also called coarse fuels.

held line:
All control line that still contains the fire when mopup is completed. Excludes lost line, natural barriers not backfired, and unused secondary lines.

high band VHF:
Radio with higher brackets of very high band frequencies of 145 to 170 megahertz.

holdover fire:
A fire that remains dormant for a considerable time. Also called sleeper fire.

hotshot crew:
Intensively trained fire crew used primarily in hand line construction (Type 1).

A particularly active part of a fire.

hourly fuels:
A way of defining the drying factor of various fuels (i.e., 10 hour fuels are 1/4 to 1 inch in thickness and take 10 hours to change their moisture content or dry out).

incendiary fire:
A wildfire willfully ignited by anyone to burn, or spread to, vegetation or property without consent of the owner or his agent.

Incident Action Plan (IAP):
Contains objectives reflecting the overall incident strategy and specific tactical actions and supporting information for the next operational period. The plan may be oral or written. When written, the plan may have a number of attachments, including: incident objectives, organization assignment list, division assignment, incident radio communication plan, medical plan, traffic plan, safety plan,, and incident map. Formerly called shift plan.

Incident Commander (IC):
The individual responsible for the management of all incident (fire) operations at the incident site.

Incident Command System (ICS):
A standardized on-scene emergency management concept specifically designed to allow its user(s) to adopt an integrated organizational structure equal to the complexity and demands of single or multiple incidents, without being hindered by jurisdictional boundaries.

indirect attack:
A method of suppression in which the control line is located some considerable distance away from the fire's active edge. Generally done in the case of a fast-spreading or high intensity fire and to utilize natural or constructed firebreaks or fuelbreaks and favorable breaks in the topography. The intervening fuel is usually backfired; but occasionally the main fire is allowed to burn to the line, depending on conditions.

Local terminology defining how the resources are deployed in extreme fire conditions using natural or manmade firebreaks.

initial attack:
The actions taken by the first resources to arrive at a wildfire to protect lives and property, and prevent further extension of the fire.

Keetch-Byram Drought Index:
Commonly-used drought index adapted for fire management applications, with a numerical range from 0 (no moisture deficiency) to 800 (maximum drought).

Angular distance, in degrees, minutes and seconds of a point north or south of the equator.

lead plane:
Aircraft with pilot used to make trial runs over the target area to check wind, smoke conditions, topography and to lead air tankers to targets and supervise their drops.

leapfrog method:
A system of organizing workers in fire suppression in which each crew member is assigned a specific task such as clearing or digging fireline on a specific section of the control line, and when that task is completed, passes other workers in moving to a new assignment.

liaison officer:
A member of the command staff responsible for coordinating with agency representatives from assisting and cooperating agencies.

line firing techniques:
Methods and tactics used to set fire along firelines or firebreaks, in wildland fire suppression or pre-suppression to get a desired effect.

The top layer of the forest floor, composed of loose debris of dead sticks, branches, twigs, and recently fallen leaves or needles, little altered in structure by decomposition.

live fuel moisture content:
Ratio of the amount of water to the amount of dry plant material in living plants.

logistics section:
The section responsible for providing facilities, services and materials for the incident.

Angular distance, in degrees, minutes and seconds of a point east or west of the Greenwich meridian.

low band VHF:
Radio with lower brackets of very high band frequencies of 30 to 50 megahertz.

Fire apparatus that has less than 500 gallons of water with pump capabilities of less than 750 gallons per minute.

Minimum Impact Suppression Techniques (MIST):
The application of strategy and tactics that effectively meet suppression and resource objectives with the least environmental, cultural and social impacts.

Extinguishing or removing burning material near control lines, felling snags, and trenching logs to prevent rolling after an area has burned, to make a fire safe, or to reduce residual smoke.

mutual aid:
Assistance rendered by other than originating organization.

National Fire Danger Rating System:
A uniform fire danger rating system that focuses on the environmental factors that control the moisture content of fuels.

natural barrier:
Any area where lack of flammable material obstructs the spread of wildfires.

neighborhood watch:
Group of citizens living in the same area who join together to protect one another through routine observation of the area where they live for criminal activity.

Trade name for a fire resistant synthetic material used in the manufacturing of flight suits and pants and shirts used by firefighters. Aramid is the generic name.

non-attainment area:
An area identified by an air quality regulatory agency through ambient air monitoring (and designated by the Environmental Protection Agency), that presently exceeds federal ambient air standards.

normal fire season
1. A season when weather, fire danger, and number and distribution of fires are about average.
2. Period of the year that normally comprises the fire season.

operations section:
The section responsible for all tactical operations at the incident. Includes branches, divisions and/or groups, task forces, strike teams, single resources and staging areas.

Anything intentionally dropped or intended for dropping from any aircraft by parachute, by other retarding devices, or by free fall.

parallel attack:
Method of fire suppression in which fireline is constructed approximately parallel to, and just far enough from the fire edge to enable workers and equipment to work effectively, though the fireline may be shortened by cutting across unburned fingers. The intervening strip of unburned fuel is normally burned out as the control line proceeds but may be allowed to burnout unassisted where this occurs without undue delay or threat to the fireline.

1. To travel over a given route to prevent, detect, and suppress fires.
2. To go back and forth vigilantly over a length of control line during or after its construction, to prevent breakovers, control spot fires, or extinguish overlooked hot spots.
3. A person or group who carry out patrol actions.

payments in lieu of taxes (PILOT)
Method of compensating taxing districts for tax revenue lost from land taken off the tax rolls.

planning section:
Responsible for all collection, evaluation, and dissemination of tactical information related to the incident, and for the preparation and documentation of incident action plans. The section also maintains information on the current and forecasted situation, and on the status of resources assigned to the incident. Includes the situation, resource, documentation, and demobilization units, as well as technical specialists.

1. Condition or degree of being ready to cope with a potential fire situation.
2. Mental readiness to recognize changes in fire danger and act promptly when action is appropriate.

prescribed burning:
Controlled application of fire to wildland fuels in either their natural or modified state, under specified environmental conditions, which allow the fire to be confined to a pre-determined area, and produce the fire behavior and fire characteristics required to attain planned fire treatment and resource management objectives.

A written statement defining the objectives to be attained as well as the conditions of temperature, humidity, wind direction and speed, fuel moisture, and soil moisture, under which a fire will be allowed to burn. A prescription is generally expressed as acceptable ranges of the prescription elements, and the limit of the geographic area to be covered.

Activities in advance of fire occurrence to insure effective suppression action. Includes recruiting and training, planning the organization, maintaining fire equipment and fire control improvements, and procuring equipment and supplies. See Prevention, Suppression.

Activities directed at reducing the incidences of fires that start, including public education, law enforcement, personal contact, and reduction of fuel hazards.

progressive hose-lay:
A hose-lay in which double shutoff wye (Y) valves are inserted in the main line at intervals and lateral lines are run from the wyes to the fire edge, thus permitting continuous application of water during extension of the lay.

progressive method of line construction:
A system of organizing workers to build fireline in which they advance without changing relative positions in line. There are two principal methods of applying the system:
1. Work is begun with a suitable space, such as 15 feet, between people. Whenever one crew member overtakes another, all of those ahead move one space forward and resume work on the uncompleted part of the line. The last person does not move ahead until the work is complete in assigned space. Forward progress of the crew is coordinated by a crew leader. This method or organization is variously termed moveup, stepup, bumpup, and functional.
2. Each person does one to several licks or strokes of work and moves forward a specified distance. The distance is determined by the number of people equipped with a given tool and number of licks needed per unit of line to complete the work for that tool. This method is termed one-lick.

project fire:
Usually refers to a fire requiring people and equipment beyond the resources of the protection unit on which it originates.

A device that adds a pre-determined amount of foam concentrate to water to form foam solution.

protection boundary:
The exterior perimeter of an area within which a specified fire agency has assumed a degree of responsibility for wildland fire control. It may include land in addition to that for which the agency has jurisdictional or contractual responsibility.

rate of spread:
The relative activity of a fire in extending its horizontal dimensions. It is expressed as rate of increase of the total perimeter of the fire, as rate of forward spread of the fire front, or as rate of increase in area, depending on the intended use of the information. Usually it is expressed in chains per hour or acres per hour for a specific period in the fire's history.

rear of a fire:
1. That portion of a fire spreading directly into the wind or down slope.
2. That portion of a fire edge opposite the head.
3. Slowest spreading portion of a fire edge. Also called heel of a fire.

1. Repeat burning of an area over which a fire has previously passed, but left fuel that later ignites when burning conditions are more favorable.
2. An area that has reburned.

relative humidity:
The ratio of the amount of moisture in the air, to the maximum amount of moisture that air would contain if it were saturated. The ratio of the actual vapor pressure to the saturated vapor pressure.

1. The chance of fire starting as determined by the presence and activity of causative agents.
2. A causative agent.
3. (NFDRS) A number related to the potential number of firebrands to which a given area will be exposed during the rating day.

As used in fire protection assessment planning, the potential of natural or accidental ignition to occur within a fire management landscape. Risk is determined based on land use patterns and is categorized as high, moderate or low.

The accumulation of living and dead ground and under story vegetation, especially grasses, forest litter, and draped dead needles, sometimes with addition of underbrush, such as palmetto, gallberry, and waxmyrtle. Most often used for southern pine types.

running fire:
Behavior of a fire spreading rapidly with a well-defined head.

safety island:
An area used for escape in the event the line is outflanked or in case a spot fire causes fuels outside the control line to render the line unsafe. In firing operations, crews progress so as to maintain a safety island close at hand, allowing the fuels inside the control line to be consumed before going ahead.

safety zone:
An area cleared of flammable materials used for escape in the event the line is outflanked or in case a spot fire causes fuels outside the control line to render the line unsafe. In firing operations, crews progress so as to maintain a safety zone close at hand allowing the fuels inside the control line to be consumed before going ahead. Safety zones may also be constructed as integral parts of fuelbreaks; they are greatly enlarged areas which can be used with relative safety by firefighters and their equipment in the event of blowup in the vicinity.

scorch height:
Average heights of foliage browning or bole blackening caused by a fire.

scratch line:
An unfinished preliminary control line hastily established or constructed as an emergency measure to check the spread of a fire.

secondary line:
Any fireline constructed at a distance from the fire perimeter concurrently with or after a line already constructed on or near to the perimeter of the fire. Generally constructed as an insurance measure in case fire escapes control by the primary line.

size class of fire (as to size of wildland fires)
Class A: A fire of one-fourth acre or less.
Class B: A fire of more than one-fourth acre, but less than 10 acres.
Class C: A fire of 10 acres or more, but less than 100 acres.
Class D: A fire of 100 acres or more, but less than 300 acres.
Class E: A fire of 300 acres or more, but less than 1000 acres.
Class F: A fire of 1000 acres or more, but less than 5000 acres.
Class G: A fire of 5000 acres or more.

The evaluation of the fire to determine the course of action for suppression.

Behavior of a fire burning without flame and barely spreading.

A standing dead tree or part of a dead tree from which at least the leaves and smaller branches have fallen. Often called stub, if less than 20 feet tall.

span of control:
The supervisory ratio of from three-to-seven individuals, with five-to-one being established as optimum.

spot burning:
A modified form of broadcast slash burning in which only the greater accumulations are fired and the fire is confined to these spots. Sometimes called "Jackpot Burning".

spot fire:
Fire ignited outside the perimeter of the main fire by flying sparks or embers.

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.

spread component:
Part of the National Fire Danger Rating System (NFDRS). A rating of the forward rate of spread of a head fire.

staging area:
Locations set up at an incident where resources can be placed while awaiting a tactical assignment on a three (3) minute available basis. Staging Areas are managed by the Operations Section.

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

strike team:
Specified combinations of the same kind and type of resources, with common communications, and a leader.

strip burning:
1. Burning by means of strip firing.
2. In hazard reduction, burning narrow strips of fuel and leaving the rest of the area untreated by fire.

strip firing:
Setting fire to more than one strip of fuel and providing for the strips to burn together. Frequently done in burning out against a wind where inner strips are fired first to create drafts which pull flames and sparks away from the control line.

stump jumper:
Local terminology for a large brush truck, usually a military type six wheel drive vehicle.

suppress a fire:
The most aggressive wildfire suppression strategy leading to the total extinguishment of a wildfire.

All the work of extinguishing or confining a fire beginning with its discovery.

suppression crew:
Two or more firefighters stationed at a strategic location, for initial action on fires. Duties are essentially the same as those of individual firefighters.

suppression firing:
Intentional application of fire to speed up or strengthen fire suppression action on wildfires. Types of suppression firing include burning out, counter firing, and strip burning.

surface fire:
Fire that burns surface litter, other loose debris of the forest floor, and small vegetation.

1. A worker who assists fallers and/or sawyers by clearing away brush, limbs and small trees. Carries fuel, oil and tools and watches for dangerous situations.
2. A worker on a dozer crew who pulls winch line, helps maintain equipment, etc., to speed suppression work on a fire.

task force:
Any combination of single resources assembled for a particular tactical need, with common communications and a leader.

test fire:
A prescribed fire set to evaluate such things as fire behavior, detection performance, control measures.

The burning of the foliage of a single tree or a small group of trees, from the bottom up.

unacceptable fire risk:
Level of fire risk above which specific action is deemed necessary to protect life, property and resources.

unified command:
In ICS, unified command is a unified team effort which allows all agencies with jurisdictional responsibility for the incident, either geographical or functional, to manage an incident by establishing a common set of incident objectives and strategies. This is accomplished without losing or abdicating authority, responsibility, or accountability.

As used in fire protection assessment planning, are natural and developed resources (e.g., archeological sites, urban interface) that are developed through an inventory and identification process, then located on a map and their ability to interact with fire determined.

Natural resources, improvements, or other values that may be jeopardized if a fire occurs; estimated damages and befits that may result from fires in a particular pre-suppression or suppression situation.

variable danger:
Resultant of all fire danger factors that vary from day to day, month to month, or year to year; (e.g., fire weather, fuel moisture content, condition of vegetation, variable risk).

vertical fuel arrangement:
Fuels above ground and their vertical continuity, which influences fire reaching various levels or vegetation strata. Also called fuel ladders.

visibility distance:
Maximum distance at which a smoke column of specified size and density can be seen and recognized as smoke by the unaided eye.

water supply map:
A map showing location of suppliers of water readily available for pumps, tanks, trucks, camp use, etc.

wet line:
A line of water, or water and chemical retardant, sprayed along the ground, and which serves as a temporary control line from which to ignite or stop a low intensity fire.

wetting agent:
A chemical that when added to water reduces the surface tension of the solution and causes it to spread and penetrate exposed objects more effectively than the untreated water.

wet water:
Water with added chemicals, called wetting agents, that increases waters spreading and penetrating properties, due to reduction in surface tension.

A fire occurring on wildland that is not meeting management objectives and thus requires a suppression response.

Wildfire Task Force:
A entity created through a resolution passed by the Central Pine Barrens Commission on November 8, 1995, that was subsequently modified on December 6, 1995 and January 29, 1997 and March 11, 1998, to undertake pre-fire planning for wildfire suppression response as called for in the Central Pine Barrens Comprehensive Land Use Plan. The Task Force is headed by a chair and co-chairs and its members include representatives from all volunteer fire departments with jurisdiction in the Core Preservation Area of the Central Pine Barrens, private, state and local agencies with vested interest in fire protection of the Central Pine Barrens, fire marshals from the Towns of Brookhaven, Southampton and Riverhead, and the Central Pine Barrens Commission's Law Enforcement Council and Protected Lands Council.

An area in which development is essentially non-existent, except for roads, railroads, powerlines, and similar transportation facilities. Structures, if any, are widely scattered.

wildland-urban interface:
The line, area, or zone where structures and other human development meet or intermingle with undeveloped wildland or vegetative fuels.