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NWCG Glossary of Wildland Fire (PMS 205)

Title Steward Status Definition
unauthorized passenger NIAC National Interagency Aviation Committee Approved

All personnel who are not official or unofficial passengers are considered unauthorized passengers and are not authorized to be transported in any aircraft owned or operated by or on behalf of the government.

unavailable Proposed New

The resource is not available to fill a resource order request.

unavailable (transferred) Proposed New

The resource has been transferred to another dispatch, but the transfer has not been completed.

uncontrolled airport NIAC National Interagency Aviation Committee Approved

Airport not having an approved agency with radio communications to direct aircraft take-offs and landings.

uncontrolled fire IOSC Incident Operations Subcommittee Approved

Any fire which threatens to destroy life, property, or natural resources, and (a) is not burning within the confines of firebreaks, or (b) is burning with such intensity that it could not be readily extinguished with ordinary tools commonly available.

under investigation CEPC Communication, Education, and Prevention Committee In Development
underburn FUSC Fire Use Subcommittee Approved

A fire that consume surface fuels but not the overstory canopy.

undercut line IOSC Incident Operations Subcommittee Approved

A fireline below a fire on a slope. Should be trenched to catch rolling material.

understory burning FUSC Fire Use Subcommittee Approved

Prescribed burning under a forest canopy.

undetermined CEPC Communication, Education, and Prevention Committee In Development

Refers to wildfire incidents where an investigation did not identify a clear or definitive cause of origin.

unified area command ICSC Incident Command Subcommittee Approved

A unified area command is established when incidents under an area command are multijurisdictional.

unified command NIMSIC National Incident Management System Integration Committee Approved

Established when more than one agency has incident jurisdiction or when incidents cross political jurisdictions. This is accomplished by establishing a common set of incident objectives and strategies, without losing or abdicating authority, responsibility, or accountability.

Unified Ordering Point IBC Incident Business Committee Approved

Single location through which all incident resource orders are processed.

unique fire identifier NCSC National Coordination System Committee Approved

A unique identifier assigned to each wildland fire.

unique fire report identifier FRSC Fire Reporting Subcommittee Approved

A code that uniquely identifies a particular fire report.

Unit

lowest in hierarchy, Relates to Agencies, Regions

unit (generic) NIMSIC National Incident Management System Integration Committee Approved

The organizational element with functional responsibility for a specific activity within the Planning, Logistics, and Finance/Administration Sections in ICS.A generic term that represents an organizational entity that only has meaning when it is contextualized by a descriptor, e.g. jurisdictional.

unit identifier UIB Unit Identifier Board Approved

A code used within the interagency incident management community to uniquely identify a particular governmental or non-government organizational unit recognized by NWCG as a wildland fire or all-risk cooperator.

unity of command NIMSIC National Incident Management System Integration Committee Approved

A NIMS guiding principle stating that each individual involved in incident management reports to and takes direction from only one person.

unity of effort LC Leadership Committee Approved

A command philosophy that encourages leaders to work together to find common ground and act in the best interest of those responding to the incident, the public, and the resources that are threatened.

Universal Transverse Mercator easting coordinates Approved

Grid coordinates expressed as a distance in meters to the east.

Universal Transverse Mercator northing coordinates Approved

Coordinates measured relative to the equator.

Universal Transverse Mercator Zone Approved

A division of the Earth's surface into 60 north-south zones, each 6 degrees of longitude wide.

unknown CEPC Communication, Education, and Prevention Committee In Development

Used when the actual value is unavailable, uncertain or yet to be determined. It indicates that the informaiton is missing or not applicable rather than representing an error or invalid entry.

unlined fire hose ETC Equipment Technology Committee Approved

Hose commonly of cotton, linen, or synthetic fiber construction without rubber tube or lining, often used for wildfires because of its light weight and self protecting (weeping) characteristics; such hose is attached to first-aid standpipes in buildings. At a specified flow, friction loss in unlined hose of a stated diameter is about twice that of lined fire hose. 

unprotected lands IFPC Interagency Fire Planning Committee Approved

Areas for which no fire organization has responsibility for management of a wildfire authorized by law, contract, or personal interest of the fire organization (e.g., a timber or rangeland association). 

unspecified shooting CEPC Communication, Education, and Prevention Committee In Development
upper level (cold) low FWS Fire Weather Subcommittee Approved

Upper Level Disturbance, Cold Low Aloft: A circulation feature of the upper atmosphere where pressure, at a constant altitude, is lowest. Winds blow counter-clockwise around the center in an approximately circular pattern. Upper level lows are usually quite small. The mechanics of these upper lows is such that a pool of cool moist air always accompanies their development. There is often no evidence of low pressure at the earth's surface. An upper low may exist above a surface high pressure system. 

upper level (cold) trough FWS Fire Weather Subcommittee Approved

Trough, Trough Aloft, Upper Level [Cold] Low: An elongated area of relatively low pressure, at constant altitude, in the atmosphere. The opposite of an upper level ridge. Upper level troughs are usually oriented north-south with the north end open. That is, air currents moving from west to east around the earth flow around three sides of the trough then turn eastward rather than toward the west, as in the case of a closed circulation. A large upper level trough may have one or more small upper level closed low circulation systems within it. 

upper level high FWS Fire Weather Subcommittee Approved

Upper High, High Aloft, Upper Level Ridge: A circulation feature of the upper atmosphere where pressure, at a constant altitude, is higher than in the surrounding region. Winds blow clockwise around an upper level high. Air in an upper level high is usually subsiding. This results in comparatively warm dry air with light winds over a large area. An upper level high may exist without there being high pressure at the earth's surface. 

upper level ridge FWS Fire Weather Subcommittee Approved

An elongated area of relatively high pressure, at a constant altitude, in the atmosphere. The opposite of an upper level trough. Upper level ridges are often oriented north-south, alternating between upper level troughs, however, during summer they may assume random orientations and vast dimensions. 

urban search/rescue/recovery (event) NCSC National Coordination System Committee Approved

An event dealing with a search, and/or rescue, and/or recovery in an urban setting.

use level ETC Equipment Technology Committee Approved

The appropriate ratio of liquid foam concentrate to water recommended by the chemical manufacturer for each class of fire, usually expressed as a percent (such as 0.5%).

use of wildland fire FMB Fire Management Board Approved

Management of wildfire or prescribed fire to meet resource objectives specified in land/resource management plans.

useful load NIAC National Interagency Aviation Committee Approved

Maximum computed gross weight minus equipped weight of a helicopter.

v pattern CEPC Communication, Education, and Prevention Committee Approved

Characteristics fire cone-shaped pattern left by a fire on a wall, at or near its point of origin.

valley (topographic) External Source Approved

A stretch of low land lying between hills or mountains which are sometimes occupied by a stream.

values at risk FUSC Fire Use Subcommittee, IFPC Interagency Fire Planning Committee Approved

The elements of a community or natural area considered valuable by an individual or community that could be negatively impacted by a wildfire or wildfire operations. These values can vary by community and can include diverse characteristics such as homes, specific structures, water supply, power grids, natural and cultural resources, community infrastructure, and other economic, environmental, and social values.

values to be protected FUSC Fire Use Subcommittee, IFPC Interagency Fire Planning Committee Approved

Include property, structures, physical improvements, natural and cultural resources, community infrastructure, and economic, environmental, and social values.

vapor suppression ETC Equipment Technology Committee Approved

Creating a seal with foam which prevents a release of flammable vapors from fuels.

variable FWS Fire Weather Subcommittee Approved

Any changing characteristic; in statistics, a measurable characteristic of an experimental unit.

variable ceiling FWS Fire Weather Subcommittee Approved

A ceiling of less than 3,000 feet (900 m) which rapidly increases or decreases in height by one or more reportable values during the period of observation.

variable danger FDSC Fire Danger Subcommittee Approved

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).

variable sky condition FWS Fire Weather Subcommittee Approved

A sky condition that varies between reportable values of sky cover amounts during the period of observation.

variable visibility FWS Fire Weather Subcommittee Approved

A condition when the prevailing visibility is less than 3 miles (5 km) and rapidly increases and decreases by one or more reportable values during the period of observation.

variable wind direction FWS Fire Weather Subcommittee Approved

Wind direction which varies by 60 degrees or more during the period of time the wind direction is being determined.

vectors FENC Fire Environment Committee Approved

Directions of fire spread as related to rate of spread calculations (in degrees from upslope).

vegetation contact CEPC Communication, Education, and Prevention Committee In Development

Related to vegetation making physical contact with an ignition source such as a power line or electric fence.

Vegetation Departure Percentage / Index

The vegetation departure index is displayed on actuals, and is an index on the FRCC. The vegetation departure percentage is displayed on estimated treatments and activities and is a percentage.

vegetative regeneration FUSC Fire Use Subcommittee Approved

Development of new aboveground plants from surviving plant parts, such as by sprouting from a root crown or rhizomes. Even if plants form their own root system, they are still genetically the same as the parent plant.

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