The following acronyms and technical terms are used during the Interagency satellite broadcast. A more complete Acronyms and Glossary (pdf) list is also available.

administrative appeal - a request to a higher authority (typically within the Federal agency or at the Departmental level) to review of a Record of Decision (ROD). In most cases, the administrative appeal processes (defined in law or regulations) is exhausted before an appellant may initiate court action against the decision.

agency/public review - a mandatory, systematic, documented 30 day period after a notice of availability is published in a local newspaper, provided for local, state, tribal and Federal agencies, as well as the general public, to review and comment on a preliminary draft General Conformity Determination (see 40 CFR 51.855, 51.856, 91.155 and 91.156).

air conformity - each Federal agency must demonstrate that its actions (either directly or by providing financial assistance, licensing, permitting or approving any activity) within a designated maintenance or nonattainment area will: (1) conform to an enforceable state, tribal or Federal implementation plan; (2) will not cause or contribute to new violations of an ambient standard; (3) will not increase the severity or frequency of existing violations; and (4) will not otherwise delay achieving attainment of the national ambient air quality standards (NAAQS; see 40 CFR parts 51 and 93). Federal actions requiring funding or approval from the U.S. Department of Transportation, the Federal Highway Administration or the Federal Transit Administration are subject to the EPA Transportation Conformity regulations. All other Federal actions are subject to the EPA General Conformity regulations.

APCD or Air Pollution Control District - a county agency with authority to regulate air pollutant emission sources, typically governed by an air pollution control district board composed of the elected county officials (Compare to AQMD).

air quality modeling - a mathematical tool used to predict the relationship between air pollutant emissions and resultant air quality, based on the simulation of atmospheric transport, dispersion, transformation and deposition.

air quality impact analysis - an assessment of potential air quality impacts which would result from an anticipated Federal action, based upon assumed engineering specifications, air pollutant emissions, meteorological conditions, atmospheric transport, transformation, dispersion, and control measures.

AQMD or Air Quality Management District - a group of counties, portions of counties, or an individual county specified by law with authority to regulate air pollutant emission sources, typically governed by a regional air pollution control board composed of elected officials from within the District (Compare to APCD).

ambient - the unconfined portion of the atmosphere located outside of structures, and particularly accessible to the public. Often used interchangeably with outdoor air.

AP-42 or Compilation of Air Pollutant Emission Factors, Fifth Edition, Volume I: Stationary Point and Area Sources - a document of air pollutant emission factors, continually revised by EPA, and used to estimate potential total emissions based on engineering design values.

attainment area - a geographic area which has consistently complied with a specific national ambient air quality standard (NAAQS), based upon a history of air quality monitoring. An area may be in attainment for one pollutant while in nonattainment area for others.

averaging time - the time period established for specific national ambient air quality standards, which must also be used when interpreting air quality monitoring data. National ambient air quality standards have different maximum levels for different averaging times.

CO or carbon monoxide - a colorless, odorless gas resulting from the incomplete combustion of fossil fuels. Over 80 per cent of CO emitted in urban areas is contributed by motor vehicles. CO interferes with the blood's ability to carry oxygen to the body's tissues, and results in numerous adverse health effects. CO is a criteria pollutant.

cause or contribute - a Federal action that may either: (1) cause a new violation of a national ambient air quality standard (NAAQS) within a nonattainment or maintenance area which would otherwise not be in violation of the standard during if the Federal action were not taken; or (2) contribute, in conjunction with other reasonably foreseeable actions, to a new violation of a NAAQS within a nonattainment or maintenance area by increasing the frequency or severity of a new violation.

Clean Air Act - established by Congress (P.L. 84-159 dated July 14, 1955) to generally encourage or otherwise promote reasonable Federal, state, and local governmental actions to prevent air pollution, and specifically to: (1) protect and enhance air quality in a manner to promote the public health and welfare; (2) initiate and accelerate national research and development to prevent and control air pollution; (3) provide technical and financial assistance to air regulatory agencies; and (4) encourage and assist operation of regional air pollution prevention and control programs.

conformity analysis - where the conformity regulations are determined to be applicable to a proposed Federal action, an analysis is necessary to: (1) quantify potential direct and indirect air pollutant emissions by using site-specific engineering specifications; (2) evaluate whether the total anticipated emissions would be "regionally significant;" (3) identify where potential emissions can be reduced through binding and enforceable mitigation measures; (4) support inclusion of the proposed activity in an enforceable implementation plan by the air regulatory agency; or (5) demonstrate the action and similar activities can be "presumed to conform." A separate analysis may not be necessary if an existing conformity analysis is adopted from another agency, or a common conformity analyses is prepared with cooperating agencies.

conformity applicability - the process by which a Federal agency evaluates if the proposed Federal action is subject to the air conformity regulations under the Clean Air Act. The conformity regulations may not be applicable if the proposed Federal action: (1) does not require Federal funds or authorization; (2) will not occur within a designated nonattainment or maintenance area; (3) emissions are specifically identified and accounted for in an applicable implementation plan; (4) emissions are not reasonably foreseeable; (5) will simply implement a decision to conduct an already conforming program; (6) total direct and indirect emissions are clearly below de minimis levels; or (7) is specifically exempted from the conformity requirements.

conformity determination - a formal regulatory process by which a Federal agency evaluates, analyzes and determines that a proposed Federal action would comply with the air conformity regulations under the Clean Air Act, including: (1) preparing a draft conformity determination; (2) notifying air regulatory agencies and the general public (through publication in a public newspaper) that a draft conformity determination is available for review; (3) allowing a 30 day written comment period; (4) preparing a final conformity determination, including responses to all comments received; and (5) notifying air regulatory agencies and the general public (again through publication in a public newspaper) that copies of the final conformity determination (including responses to comments) are available upon request. The conformity determination process may be incorporated into a concurrent NEPA document, but the analysis, notification, comment and response requirements are not automatically covered by the NEPA analyses.

control measures - methods or technology used to limit or reduce air pollutant emissions.

criteria pollutant - an air pollutant for which acceptable levels of exposure have been determined and documented (in a criteria document), and a national ambient air quality standard (NAAQS) has been established.

direct emission - emissions of an air pollutant (or its precursors) that are caused by, and occur at the same time and place, as a Federal action.

emission permit - legal instrument issued by a regulatory agency authorizing the emission of air pollutants from any activity covered under an applicable implementation plan, including emission limits, control measures, monitoring requirements, fees, etc.

enforceability - legal ability of a regulatory agency to establish and enforce a wide range of air quality requirements, vested under the U.S. Constitution, legislated by Congress, and authorized by EPA through an approved implementation plan.

EPA or U.S. Environmental Protection Agency - an independent Federal agency responsible for implementing Federal environmental management laws, conducting environmental management research, establishing national ambient air quality standards (NAAQS), funding and providing technical assistance to local, state and tribal air quality regulatory agencies, and assuring that those agencies adequately implement air quality requirements (or directly implement the air quality requirements when those agencies fail to meet their regulatory obligations).

exceedance - air pollutant levels above regulatory limits. An exceedance may not be in violation if the regulation, such as national ambient air quality standards (NAAQS), allow air quality levels to occasionally be above the "standard." For example, the 24-hour fine particulate matter standard allows for one exceedance annually without violating the standard.

Federal action - any activity directly engaged in by a Federal agency, or any activity that a Federal agency supports in any way (including providing financial assistance, licenses, permits, or approves). Where there is no direct Federal action, but simply a supporting action, the relevant activity is the part, portion, or phase of the non-Federal undertaking which requires a Federal permit, license, or approval.

Federal agency - any department, agency, or instrumentality of the Federal Government.

FIP or Federal Implementation Plan - in the absence of a proposed State or Tribal Implementation Plan, the EPA must prepare a detailed description of the goals, management practices, programs, regulations and standards the EPA will use to carry out its responsibilities to protect and improve air quality under the Clean Air Act. As with SIPs and TIPs, the general public has an opportunity to review and comment prior to EPA implementing a FIP.

FLM or Federal Land Manager - an agency or official charged with direct responsibility for management of an area of Federal lands (e.g. USDA-Forest Service, USDI-Bureau of Land Management, USDI-National Park Service, USDI-U.S. Fish & Wildlife Service, etc.)

general conformity - each Federal agency must demonstrate that its actions (not associated with Federal transportation-related activities) conform to an enforceable state, tribal or Federal implementation plan.

indirect emissions - emissions of an air pollutant (or its precursors) that: (1) are not a direct cause of the Federal action, but are reasonably foreseeable to occur as a result of the Federal action later in time and/or remote from the action itself; and (2) can be practically controlled by the Federal agency and will continue to be controlled due to a continuing Federal agency responsibility.

maintenance area - a former nonattainment area which has successfully taken actions to achieve the national ambient air quality standards (NAAQS) through the applicable implementation plan, and must continue to meet those standards as specified in a formal Maintenance Plan.

milestone - dates specified in the applicable implementation plan by which quantitative air quality goals must be achieved.

mitigation measures - management methods or technologies which could (potential) or would (required) be applied to a Federal action to reduce air quality impacts.

modeling protocol - a specified procedure to determine the potential effects of air pollutant emissions on air quality using a mathematical atmospheric transport and dispersion model.

NEPA or National Environmental Policy Act - Federal legislation requiring that potential significant environmental impacts are analyzed, summarized and disclosed for agency and public comment, and reviewed by a Federal agency decision maker before Federal action may be implemented (based on a Finding of No Significant Impact or a formal Record of Decision - ROD).

nonattainment area - a geographic area which has consistently violated a specific national ambient air quality standard (NAAQS), based upon a history of air quality monitoring, and must take actions necessary to meet those standards within a specific time period, as required in the applicable Implementation Plan. An area may be in nonattainment for one pollutant while in attainment area for others.

NAAQS or National Ambient Air Quality Standards - maximum outdoor concentration levels (and averaging times) of criteria air pollutants established by the EPA which will not cause unacceptable impacts to human health (primary standards) or public welfare (secondary standards).

NSR or New Source Review - a permit review process applicable to the construction and operation of new and modified major stationary sources to: (1) assure attainment of the national ambient air quality standards (NAAQS); (2) identify necessary control measures; and (3) demonstrate compliance with applicable Prevention of Significant Deterioration requirements.

NO₂ or nitrogen dioxide - a brown, acrid gas produced from burning fossil fuels, including gasoline and coal. Most NO₂ in urban areas is contributed by motor vehicles, where naturally occurring nitrogen and oxygen are raised to high temperatures through combustion, then exhausted into the atmosphere and rapidly cooled. Of the total oxides of nitrogen (NO_x) formed in combustion, nearly three fourths is NO₂, and one fourth is nitrogen oxide (NO), which combines with volatile organic compounds (VOC) to form ozone (O₃). NO₂ directly causes several adverse health effects, contributes to visibility degradation (both as a "brown cloud" and as secondary fine particulate matter), and when transformed to nitric acid, is a major component of atmospheric deposition (acid rain). NO₂ is a criteria pollutant.

O₃ or ozone - a pale blue, acrid gas formed naturally by lightning, and at 10 to 15 miles above the earth's surface where naturally occurring oxygen absorbs ultraviolet radiation and is transformed into stratospheric ozone. Ground-level emissions of oxides of nitrogen (NO_x) combine with volatile organic compounds (VOC) to form tropospheric ozone in the presence of sunlight. Ozone burns optical, nasal and lung tissues, as well as oxidizing paints and rubber products. Ozone is a criteria pollutant.

Pb or lead - chemically known as plumbum (Pb), lead is a naturally occurring soft metal which was once added to gasoline as an inexpensive way to increase the fuel's octane levels. Now banned from gasoline in the U.S., high lead concentrations are still found around individual operating and abandoned mines. Lead is a criteria pollutant which can damage the brain and nervous system, especially in young children.

PM-10 or inhalable particulate matter - a major air pollutant consisting of tiny solid or liquid particles of soot, dust, smoke, fumes, and mists. The size of the particles (10 microns or smaller, about 0.0004 inches or less) allows them to easily enter deep into the lungs where they may be deposited resulting in adverse health effects. PM-10 also contributes to visibility reduction and is a criteria air pollutant. The EPA has proposed additional fine particulate matter (PM-2.5; 2.5 microns or smaller) national ambient air quality standards (NAAQS), but implementation is delayed pending a Supreme Court decision.

precursors - air pollutants for which national ambient air quality standards (NAAQS) have not been established, but which can transform or contribute to the formation of criteria pollutants (such as oxides of nitrogen and volatile organic compounds which contribute to the formation of ozone (O₃).

primary standards - national ambient air quality standards (NAAQS) established by the EPA specifying the maximum air pollutant concentrations which may exist without unacceptable effects on human health.

PSD Class I Area - under the prevention of significant deterioration (PSD) program within attainment and unclassifiable areas, Class I Areas allow only a minimal increase in specific air pollutants above a legally defined baseline level. Class I Areas also require analysis of potential impacts to Air Quality Related Values (AQRV) such as water quality, ecosystem, historic structures, etc. Congress identified 158 mandatory Federal Class I Areas in the 1977 Clean Air Act Amendments where special visibility protection regulations are applicable.

reasonably foreseeable - projected future air pollutant emissions that can reasonably be anticipated to occur at the time a Federal action would take place. The location of such emissions should be known and the emissions quantifable, as described and documented by the Federal agency.

ROD or Record of Decision - a concise, formal public record prepared after all environmental analysis procedures under the National Environmental Policy Act (NEPA) have been completed, describing: (1) what Federal action was selected for implementation; (2) which alternative actions were also considered; (3) specifying whether all practicable means to avoid or minimize environmental harm from the selected action were adopted (or if not, why); and (4) monitoring and enforcement actions when further mitigation measures are required (see 40 CFR 1506.10).

redesignation - the formal process by which regulatory agencies recommend, and EPA approves, a change in attainment classification, such as nonattainment to maintenance, or attainment to nonattainment.

regulatory agency - local, state, and tribal government organizations authorized by EPA through an applicable implementation plan to enforce a multitude of requirements under the Clean Air Act.

secondary standards - national ambient air quality standards (NAAQS) established by the EPA specifying the maximum air pollutant concentrations which may exist without unacceptable effects to public welfare.

SIP or State Implementation Plan - a detailed description of the goals, management practices, programs, regulations and standards a state will use to carry out its responsibilities to protect and improve air quality under the Clean Air Act. The EPA must review and approve each portion of the State Implementation Plan before the state has authority to implement the plan. In addition, the general public has an opportunity to review and comment prior to plan approval.

SO₂ or sulfur dioxide - a colorless, foul smelling gas produced from burning fossil fuels, including gasoline and coal, which contain trace levels of sulfur contaminants. Most SO₂ is contributed from coal-fired power plants, copper smelters, and diesel burning motor vehicles. SO₂ can directly cause adverse health effects when sulfuric acid is formed on moist tissues, contributes to visibility degradation (as secondary fine particulate matter), and when transformed to sulfuric acid, is a major component of atmospheric deposition (acid rain). SO₂ is a criteria pollutant.

transportation conformity - each Federal agency must demonstrate that its actions associated with U.S. Department of Transportation, the Federal Highway Administration or the Federal Transit Administration activities conform to an enforceable state, tribal or Federal implementation plan.

TIP or Tribal Implementation Plan - a detailed description of the goals, management practices, programs, regulations and standards a tribe will use to carry out its responsibilities to protect and improve air quality under the Clean Air Act. The EPA must review and approve each portion of the Tribal Implementation Plan before the tribe has authority to implement the plan. In addition, the general public has an opportunity to review and comment prior to plan approval.

unclassifiable area - a geographic area which does not have a history of air quality monitoring, but is assumed to comply with a specific national ambient air quality standard (NAAQS), due to a lack of pollutant specific emission sources or due to its rural location. An area may be unclassified for one pollutant while in non-attainment area for others.

violation - air pollutant levels above regulatory limits and beyond all allowable exceptions. For example, a second exceedance of the 24-hour fine particulate matter standard would be a violation of the national ambient air quality standard (NAAQS).

VOC or volatile organic compounds - organic chemicals which produce vapors readily, at room temperature and normal atmospheric pressure. VOCs include gasoline, industrial chemicals such as benzene, and industrial solvents (such as those used in dry cleaning). Many VOCs are also hazardous air pollutants; for example, benzene causes cancer. VOCs also combine with oxides of nitrogen (NO_x) in the presence of sunlight to form ozone (O₃). However, VOC is not a criteria pollutant.