Skip to main content

NWCG Glossary of Wildland Fire (PMS 205)

Term Steward Status Definition
small aircraft AMC Aviation Management Committee Approved An aircraft of 12,500 pounds (5,669 kg) or less, maximum certificated takeoff weight.
smog FMSC Fuels Management Subcommittee, IWSC Incident Weather Subcommittee Approved Generally considered only photochemical air pollution. Originally meant a combination of smoke and fog.
smoke FISC Fire Investigation Subcommittee Approved Small particles of carbon, tarry and water vapor resulting from the incomplete combustion of carbonaceous materials such as wood, coal or oil.
smoke concentration FMSC Fuels Management Subcommittee Approved The amount of combustion products found in a specified volume of air, commonly expressed as micrograms of emission per cubic meter of air.
smoke intrusion FMSC Fuels Management Subcommittee Approved Smoke from prescribed fire entering a designated area at unacceptable levels.
smoke management FMSC Fuels Management Subcommittee, IWSC Incident Weather Subcommittee Approved The policies and practices implemented by air and natural resource managers directed at minimizing the amount of smoke entering populated areas or impacting sensitive sites, avoiding significant deterioration of air quality and violations of National Ambient Air Quality Standards, and mitigating human-caused visibility impacts in Class I areas. 
smoke pall FASC Fire Analysis Subcommittee Approved Extensive, thick blanket of smoke spreading more or less horizontally from a fire.
smoke plume FMSC Fuels Management Subcommittee, IWSC Incident Weather Subcommittee Approved The gases, smoke, and debris that rise slowly from a fire while being carried along the ground because the buoyant forces are exceeded by those of the ambient surface wind.
Smoke Sensitive Area (SSA) FMSC Fuels Management Subcommittee Approved Area in which smoke from outside sources is intolerable, for reasons such as heavy population, existing air pollution, or intensive recreation or tourist use.
smoke target FMSC Fuels Management Subcommittee Approved An area that may be adversely affected by smoke from a prescribed burn.
smoke vent height IWSC Incident Weather Subcommittee Approved Level, in the vicinity of the fire, at which the smoke ceases to rise and moves horizontally with the wind at that level.
Smoke-Induced Fog (SIF) SMSC Smoke Subcommittee Approved A dense fog (water droplets suspended in the atmosphere) that forms away from a fire site when surface smoke comprised of increased fine particulates and water vapor, combines with ambient air that is already prone to natural fog formation.
Smokey Bear PIC Public Information Management Committee, EPSC Education & Prevention Subcommittee Approved The symbol of the Cooperative Forest Fire Prevention Program since 1945. Smokey's image is protected by US Federal Law and is administered by the USDA Forest Service, the National Association of State Foresters and the Ad Council.
smoking (as a fire cause) FISC Fire Investigation Subcommittee Approved Wildfires caused by smokers from matches, lighters, tobacco, or other smoking material.
smoldering combustion FMSC Fuels Management Subcommittee Approved Combined processes of dehydration, pyrolysis, solid oxidation, and scattered flaming combustion and glowing combustion, which occur after the flaming combustion phase of a fire; often characterized by large amounts of smoke consisting mainly of tars.
smoldering combustion phase FMSC Fuels Management Subcommittee Approved Phase of combustion immediately following flaming combustion. Emissions are at twice that of the flaming combustion phase.
snag TFSC Tree Felling Subcommittee Approved A standing dead tree or part of a dead tree from which at least the leaves and smaller branches have fallen. Often known as a stub, if less than 20 feet tall.
snorkel tank AMC Aviation Management Committee Approved A fixed tank attached to the belly of the helicopter that has a pump-driven snorkel attached. The helicopter hovers over the water source with the end of the snorkel immersed, the pump then fills the tank.
soft suction ETSC Equipment/Technology Subcommittee Approved Commonly accepted term for short length of large diameter soft hose used to connect a structural or wildland engine with a hydrant. No vacuum is involved because the hose is useful only when the engine receives water at a rate of flow in excess of the demand of the pump. 
solar radiation FDSC Fire Danger Subcommittee Approved The amount of sunlight exposed to the fuels.
soot IWSC Incident Weather Subcommittee Approved Carbon dust formed by incomplete combustion.
sooting fire pattern indicator FISC Fire Investigation Subcommittee Approved Objects displaying more soot deposits on the exposed surface of the object than on the protected surface of the object indicating the direction of fire progression at that location. One of the 11 NWCG categories of fire pattern indicators.
sortie AMC Aviation Management Committee Approved Single round trip made by an airtanker from a tanker base to a fire and return.
sound warbler AMC Aviation Management Committee Approved A signaling device mounted on retardant aircraft which generates a tremulous siren sound to warn firefighters on the ground that a plane is approaching to drop retardant.
sounding (upper air sounding) IWSC Incident Weather Subcommittee Approved A sampling of upper air conditions made by means of instruments and a small radio transmitter on a free balloon. Automatic radio signals originated by action of weather instruments are sent to a ground receiver. These signals are interpreted for use in analyzing and predicting upper air conditions over a wide area of the earth. Weather elements determined at a number of altitude points as the balloon rises are temperature, atmospheric moisture, pressure, wind direction and speed. Similar soundings may be made using fixed balloons or tethersondes.
Displaying 2276 - 2300 of 2700

NWCG Latest Announcements