SWCAA Content Dictionary

This page contains the content dictionary of relevant SWCAA and air-related topics and codes. Have you wondered what SEPA, ACFM, EU or many other acronyms mean? Click on a letter to view the dictionary items that begin with that letter.





























acfm - Actual Cubic Feet per Minute 
Actual cubic feet per minute (acfm) is a unit of volumetric capacity. It is commonly used by manufacturers of blowers and compressors. This is the actual gas delivery with reference to inlet conditions, whereas cubic foot per minute (cfm) is an unqualified term and should only be used in general and never accepted as a specific definition without explanation. Since the volumetric capacity refers to the volume of air or other gas at the inlet to the unit, it is often referred to as "inlet cubic feet per minute" (icfm).

ADP - Air Discharge Permit 
A permit issued by SWCAA that permits an organization to operate an emission unit within stated emission levels. ADP's are issued to non-Title V and Title V facilities.

AIRS - Aerometric Information Retreival System 
A computer-based repository of information about airborne pollution in the U.S. It is maintained by EPA.

AOP - Air Operating Permit 
A permit issued by SWCAA that permits an organization to operate an emission unit within stated emission levels. AOP's are issued to Title V facilities.

AQMA - Air Quality Maintenance Area 
An Air Quality Maintenance Area (AQMA) is an area designated by EPA that has previously exceeded a NAAQS. A plan must be written to demonstrate how the area will prevent future exceedances of the NAAQS and maintain air quality.

AQMP - Air Quality Maintenance Plan 
Once an area has been declared an AQMA, the agency responsible for air quality must create an Air Quality Maintenance Plan (AQMP) that describes the steps the agency will take to prevent future exceedances of the NAAQS.

ASIL - Acceptable Source Impact Level 
The acceptable source impact level (ASIL) is a concentration threshold established under WAC 173-460 (toxic regulation for new sources). This concentration is established for specific pollutants and represents a threshold below which no adverse human health impacts are expected. The ASIL has an averaging period of 24-hour, annual or both.

ASTM - American Society for Testing and Materials 
ASTM International is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services. Some 12,575 ASTM voluntary consensus standards operate globally. The organization's headquarters is in West Conshohocken, Pennsylvania, about 5 mi (8.0 km) northwest of Philadelphia.


BACT - Best Available Control Technology 
Best Available Control technology (BACT), when applied to an emission unit, means an emission limitation based on the maximum degree of reduction of each pollutant. "Technology" may mean physical equipment, such as a scrubber or baghouse, or a practice, such as monitoring combustion efficiency. When BACT is determined, factors such as energy consumption, total source emission, regional environmental impact, and economic costs are taken into account. The BACT standard is significantly more stringent than the RACT standard but much less stringent than the LAER standard.

BART - Best Available Retrofit Technology 
Best Available Retrofit Technology (BART) is a concept used to address concerns over visibility and haze. Air pollutants that cause or contribute to haze include PM2.5, SO2, and NOX. for industrial facilities that emit these pollutants, but have never met or been required to control these pollutants, BART requires that existing equipment be updated with technology to reduce these emissions. To be selected as BART, a control technology must be available, technically feasible, cost effective, and improve visibility. It must also have a low chance of causing any other negative environmental effects.

Btu - British Thermal Unit 
British Thermal Unit (Btu) is a traditional unit of work equal to about 1055 joules. It is the amount of work needed to raise the temperature of one pound of water by one degree Fahrenheit. One four-inch wooden kitchen match consumed completely generates approximately 1 Btu.

This is a pollution control concept that considers multiple sources at a single facility or multiple facilities as existing under a glass "bubble". In order to maintain the regulatory status of the items within the bubble, any increase in one location must be decreased in another. Within a facility, this may mean that emissions from a new boiler might be offset by reducing the emissions from an existing process by the same amount. Bubbles are a form of emissions trading.


CARB - California Air Resources Board 
The California Air Resources Board (CARB) is the California agency that is responsible for enforcing federal, state and local outdoor air quality standards and regulations.The governing board is made up of eleven members appointed by the state's governor. Half of the appointees are experts in professional and science fields such as medicine, chemistry, physics, meteorology, engineering, business, and law. Others represent the pollution control agencies of regional districts within California - Greater Los Angeles Area, San Francisco Bay area, San Diego, the San Joaquin Valley, and other districts.

CEMS - Continuous Emission Monitor System 
A Continuous Emission Monitoring System (CEMS) is an instrument that monitors the concentration of a particular constituent of an exhaust gas, typically oxygen, carbon monoxide, carbon dioxide, NOX, or SO2. This information may be used to adjust combustion control or process parameters and are often used as a means to comply with air emission standards.

CFC - Chloroflourocarbons 
A CFC is an organic compound that contains only carbon, chlorine, and fluorine, produced as volatile derivative of methane, ethane, and propane. They are also commonly known by the DuPont brand name Freon. The most common representative is dichlorodifluoromethane (R-12 or Freon-12). Many CFCs have been widely used as refrigerants, propellants (in aerosol applications), and solvents. Because CFCs contribute to ozone depletion in the upper atmosphere, the manufacture of such compounds has been phased out under the Montreal Protocol, and they are being replaced with other products such as hydrofluorocarbons.

cfm - Cubic Feet per Minute 
The cubic foot is a unit of volume. It is defined as the volume of a cube with sides of one foot (0.3048 m) in length. Its volume is 28.3168 liters or about 135 of a cubic meter.

CFR - Code of Federal Regulations 
The Code of Federal Regulations (CFR) is the codification of the general and permanent rules and regulations (sometimes called administrative law) published in the Federal Register by the executive departments and agencies of the federal government of the United States. The CFR is divided into 50 titles that represent broad areas subject to federal regulation.

CO - Carbon Monoxide 
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. It is toxic when encountered in concentrations above about 35 ppm, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. CO is a criteria air pollutant and is subject to a NAAQS.

CO2 - Carbon Dioxide 
Carbon dioxide (CO2) is a colorless and odorless gas vital to life on Earth. This naturally occurring chemical compound is composed of a carbon atom covalently double bonded to two oxygen atoms. Natural sources include volcanoes, hot springs and geysers, and it is freed from carbonate rocks by dissolution in water and acids. Because carbon dioxide is soluble in water, it occurs naturally in groundwater, rivers and lakes, in ice caps and glaciers and also in seawater. It is present in deposits of petroleum and natural gas.

CO2e - Carbon Dioxide Equivalent 
A metric measure used to compare the emissions from various greenhouse gases based upon their global warming potential (GWP). Carbon dioxide equivalents are commonly expressed as "million metric tons of carbon dioxide equivalents (MMTCO2Eq)." The carbon dioxide equivalent for a gas is derived by multiplying the tons of the gas by the associated GWP.

COH - Coefficient of Haze 
The coefficient of haze (also known as smoke shade) is a measurement of visibility interference in the atmosphere. One way to measure this is to draw about 1000 feet of air sample through an air filter and obtain the radiation intensity through the filter. The coefficient is then calculated based on the absorbance formula: COH = −100 log10 * [I1I0] where I1 is the radiation (400 nm light) intensity transmitted through the sampled filter, and I0 is the radiation intensity transmitted through a clean (control) filter.

COMS - Continuous Opacity Monitoring System 
Opacity is a reduction of visibility, where zero is no obscurement and 100% is complete obscurement. A continuous Opacity Monitoring System (COMS) is an instrument that uses a light source of a known brightness that is passed through an exhaust stack. A detector determines how much light is decreased, which is related to how opaque the exhaust stream is. A continuous readout shows how the opacity varies over very short periods, such as a 1-minute average.


DEQ - Department of Environmental Quality (State of Oregon) 
The Oregon Department of Environmental Quality (DEQ) is the chief regulatory agency of the government responsible for protecting and enhancing the state's natural resources and managing sanitary and toxic waste disposal. The agency employs approximately 700 scientists, engineers, technicians, administrators, and environmental specialists. It has headquarters in Portland, regional administrative offices in Bend, Eugene, and Portland; and field offices in Coos Bay, Grants Pass, Hermiston, Medford, Pendleton, Roseburg, Salem, and The Dalles.

DOE - Department of Ecology (State of Washington) 
The Washington State Department of Ecology, or simply, Ecology, is an environmental regulatory agency for the State of Washington. The department administers laws and regulations pertaining to the areas of water quality, water rights and water resources, shoreline management, toxics clean-up, nuclear waste, hazardous waste and air quality. It also conducts monitoring and scientific assessments.

dscfm - Dry Standard Cubic Foot per Minute 
Because there are many factors that affect how air behaves, it is necessary to correct some measurements so that they can be compared. Exhaust temperatures and pressure vary and so the flows are adjusted to Standard conditions (68°F and 1 atm). If there is substantial moisture in the exhaust, it can affect the mass of material flowing out of an exhaust, so flows are often corrected to "dry" conditions at 0% moisture by multiplying the "wet" flow by 100 ⁄ (100 − %moisture).


EF - Emission Factor 
An emission factor (EF) is a value that translates a quantity or activity rate into an emissions amount. For example if 10 lb of emissions are generated for each 2 gallons of fuel burned, then the emission factor would be 5 lb/gal. Emission factors may be generated experimentally through testing, by using mass balance, estimation techniques, or other observations.

EFSEC - Energy Facility Site Evaluation Council 
The Energy Facility Site Evaluation Council (EFSEC) is a WA State government agency that provides "one stop" siting and permitting for large energy and petroleum facilities.

EI - Emission Inventory 
An emission inventory is an accounting of the amount of pollutants discharged into the atmosphere. An emission inventory usually contains the total emissions for one or more specific greenhouse gases or air pollutants, originating from all source categories in a certain geographical area and within a specified time span, usually a specific year.

EIS - Environmental Impact Statement 
An environmental impact statement (EIS), under United States environmental law, is a document required by the National Environmental Policy Act (NEPA) for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making. It describes the positive and negative environmental effects of a proposed action, and it usually also lists one or more alternative actions that may be chosen instead of the action described in the EIS. Several U.S. state governments require that a document similar to an EIS be submitted to the state for certain actions. For example, in California, an Environmental Impact Report (EIR) must be submitted to the state for certain actions, as described in the California Environmental Quality Act (CEQA). One of the primary authors of the act is Lynton K. Caldwell.

EPA - Environmental Protection Agency 
The United States Environmental Protection Agency (EPA or sometimes USEPA) is an agency of the federal government which was created for the purpose of protecting human health and the environment by writing and enforcing regulations based on laws passed by Congress. The EPA was proposed by President Richard Nixon and began operation on December 2, 1970, after Nixon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its Administrator, who is appointed by the president and approved by Congress. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank.

EPCRA - Emergency Planning and Community Right-to-Know Act 
The Emergency Planning and Community Right-to-Know Act (EPCRA) is a federal law (42 USC Chapter 116) was created to help communities plan for chemical emergencies. It also requires industry to report on the storage, use and releases of hazardous substances to federal, state, and local governments. EPCRA requires state and local governments, and Indian tribes to use this information to prepare their community from potential risks.

ERC - Emission Reduction Credit 
Emissions trading or cap and trade is a government-mandated, market-based approach to controlling pollution by providing economic incentives for achieving reductions in the emissions of pollutants. Various countries, states and groups of companies have adopted such trading systems, notably for mitigating climate change. A central authority (usually a governmental body) allocates or sells a limited number of permits to discharge specific quantities of a specific pollutant per time period. Polluters are required to hold permits in amount equal to their emissions. Polluters that want to increase their emissions must buy permits from others willing to sell them. Financial derivatives of permits can also be traded on secondary markets. In theory, polluters who can reduce emissions most cheaply will do so, achieving the emission reduction at the lowest cost to society. Cap and trade is meant to provide the private sector with the flexibility required to reduce emissions while stimulating technological innovation and economic growth.


FCAA - Federal Clean Air Act 
The Federal Clean Air Act (FCAA) is a law designed to control air pollution on a national level. It is one of the United States' first and most influential modern environmental laws, and one of the most comprehensive air quality laws in the world. As with many other major U.S. federal environmental statutes, it is administered by EPA, in coordination with state, local, and tribal governments. Its implementing regulations are codified at 40 C.F.R. Subchapter C, Parts 50-97.

FFY - Federal Fiscal Year 
Since 1976, the federal fiscal year is the 12-month period starting on October 1 and ending on September 30.

FR - Federal Register 
The Federal Register (FR) is the official journal of the federal government of the United States that contains government agency rules, proposed rules, and public notices. It is published daily, except on federal holidays. The final rules promulgated by a federal agency and published in the Federal Register are ultimately reorganized by topic or subject matter and codified in the Code of Federal Regulations (CFR), which is updated annually.

FY - Fiscal Year (SWCAA) 
SWCAA's fiscal year is the 12-month period starting on July 1 and ending on June 30.


GC - Gas Chromatography 
Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture (the relative amounts of such components can also be determined). In some situations, GC may help in identifying a compound. In preparative chromatography, GC can be used to prepare pure compounds from a mixture.

GEP - Good Engineering Practice 
"Good engineering practice" or "GEP" is engineering and technical activities that ensure that a company manufactures products of the required quality as expected (e.g., by the relevant regulatory authorities). Good engineering practices are to ensure that the development and/or manufacturing effort consistently generates deliverables that support the requirements for qualification or validation. Good engineering practices are applied to all industries that require engineering.

GHG - Greenhouse Gases 
A greenhouse gas (sometimes abbreviated GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide (N2O), and ozone. Without greenhouse gases, the average temperature of Earth's surface would be about 0°F, rather than present average of 59°F.

gr/dscf - Grains per Dry Standard Cubic Foot 
This unit is commonly used for equipment that emits particulate matter, generally in very low concentrations. A grain is a unit of measure representing 17000 of a pound. As some equipment has exhaust that contains water, the exhaust flow is corrected to 0% moisture.


H2S - Hydrogen Sulfide 
Hydrogen sulfide (chemical formula H2S) is a colorless gas with the characteristic foul odor of rotten eggs; it is heavier than air, very poisonous, corrosive, flammable, and explosive.

HAP - Hazardous Air Pollutant 
Hazardous air pollutants (HAPs) are those pollutants known to cause cancer and other serious health impacts. The FCAA requires EPA to regulate toxic air pollutants, also known as air toxics, from categories of industrial facilities


IMPROVE - Interagency Monitoring of Protected Visual Environments 
IMPROVE is a cooperative measurement effort managed by a Steering Committee that consists of representatives from EPA, NPS, USFS, FWS, BLM, NOAA, four organizations representing state air quality organizations (NACAA, WESTAR, NESCAUM, and MARAMA), and three Associate Members: AZ DEQ, Env. Canada, and the South Korea Ministry of Environment. The IMPROVE program establishes current visibility and aerosol conditions in mandatory Class I areas; identifies chemical species and emission sources responsible for existing man-made visibility impairment; documents long-term trends in visibility; and provides regional haze monitoring representing all visibility-protected federal Class I areas, where practical.


LAER - Lowest Achievable Emission Rate 
Similar to RACT and BACT, Lowest achievable emissions rate (LAER) is applied to an emission unit or process and is a method of emission control. As it is implied, LAER represents the lowest emission rate that is achievable. Cost is generally not considered as a factor for eliminating a particular emission technology. LAER is typically only employed in severe non-attainment areas when air quality is significantly compromised and is the most stringent air pollution standard above BACT and RACT.

LUST - Leaking Underground Storage Tanks 
A leaking underground storage tank (LUST) is one of the more serious environmental impacts to soil and water contamination. These sources are typically encountered at gasoline stations, but also occur at industrial facilities. Cleanup can be complicated and costly.


MACT - Maximum Achievable Control Technology 
The FCAA requires EPA to regulation HAP from categories of industrial facilities. In the first phase of regulation, EPA established Maximum Achievable Control Technologies (MACTs) which are technology standards based on emissions levels that are already being achieved by the best controlled and lower emitting sources in an industry or source category. These MACTs are authorized by Section 112 of the FCAA and the regulations are published in 40 CFR 61.

MOBILE Model -  
A software tool for predicting gram per mile emissions of hydrocarbons, carbon monoxide, oxides of nitrogen, carbon dioxide, particulate matter and air toxics from cars, trucks, and motorcycles under various conditions.

MOU - Memorandum of Understanding 
A memorandum of understanding (MoU) describes a bilateral or multilateral agreement between two or more parties. It expresses a convergence of will between the parties, indicating an intended common line of action. It is often used in cases where parties either do not imply a legal commitment or in situations where the parties cannot create a legally enforceable agreement. It is a more formal alternative to a gentlemen's agreement. Whether or not a document constitutes a binding contract depends only on the presence or absence of well-defined legal elements in the text proper of the document (the so-called "four corners"). The required elements are: offer and acceptance, consideration, and the intention to be legally bound (animus contrahendi). In the U.S., the specifics can differ slightly depending on whether the contract is for goods (falls under the Uniform Commercial Code [UCC]) or services (falls under the common law of the state).

MSA - Metropolitan Statistical Area 
In the United States, a metropolitan statistical area (MSA) is a geographical region with a relatively high population density at its core and close economic ties throughout the area. Such regions are neither legally incorporated as a city or town would be, nor are they legal administrative divisions like counties or separate entities such as states. As such, the precise definition of any given metropolitan area can vary with the source. A typical metropolitan area is centered on a single large city that wields substantial influence over the region (e.g., Chicago or Atlanta). However, some metropolitan areas contain more than one large city with no single municipality holding a substantially dominant position (e.g., Dallas–Fort Worth metroplex, Norfolk-Virginia Beach (Hampton Roads), Riverside–San Bernardino (Inland Empire) or Minneapolis–Saint Paul). MSAs are defined by the Office of Management and Budget (OMB) and used by the Census Bureau and other federal government agencies for statistical purposes.

MW - Megawatt 
The megawatt is equal to one million (106) watts. Many events or machines produce or sustain the conversion of energy on this scale, including large electric motors; large warships such as aircraft carriers, cruisers, and submarines; large server farms or data centers; and some scientific research equipment, such as supercolliders, and the output pulses of very large lasers. A large residential or commercial building may use several megawatts in electric power and heat. On railways, modern high-powered electric locomotives typically have a peak power output of 5 or 6 MW, although some produce much more. The Eurostar, for example, uses more than 12 MW, while heavy diesel-electric locomotives typically produce/use 3 to 5 MW. U.S. nuclear power plants have net summer capacities between about 500 and 1300 MW.


NAA - Nonattainment Area 
In United States environmental law, a nonattainment area (NAA) is an area considered to have air quality worse than the NAAQS. NAAs must have and implement a plan to meet the standard, or risk losing some forms of federal financial assistance. An area may be NAAs for one pollutant and an attainment area for others.

NAAQS - National Ambient Air Quality Standards 
The US National Ambient Air Quality Standards (NAAQS) are standards established by the United States Environmental Protection Agency under authority of the Clean Air Act (42 U.S.C. 7401 et seq.) that apply for outdoor air throughout the country. Primary standards are designed to protect human health, with an adequate margin of safety, including sensitive populations such as children, the elderly, and individuals suffering from respiratory diseases. Secondary standards are designed to protect public welfare from any known or anticipated adverse effects of a pollutant. A district meeting a given standard is known as an "attainment area" for that standard, and otherwise a "non-attainment area".

NACAA - National Association of Clean Air Agencies 
NACAA is the national, non-partisan, non-profit association of air pollution control agencies in 40 states, the District of Columbia, four territories and 116 metropolitan areas. The association serves to encourage the exchange of information, to enhance communication and cooperation among federal, state, and local regulatory agencies, and to promote good management of our air resources.

NAICS - North American Industry Classification System 
Like the SIC code, the North American Industry Classification System (NAICS) code is used to classify businesses for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. economy. This code is a 6-digit code that identifies business types, materials, commodities, and activities. It has generally replaced the older system of SIC codes.

NAMS - National Air Monitoring Station 
A National Air Monitoring Station (NAMS), which is generally also a SLAMS, is an air pollution monitor that measures ambient concentrations of those pollutants for which NAAQS have been established in 40 CFR Part 50 and that meets federal siting requirements under 40 CFR 58. Information from the NAMS is used to designate nonattainment and attainment areas.

NATA - National Air Toxics Assessment 
EPA collects emission information for facilities, mobile sources, and area sources from States, Locals, and Tribes for use in a National Air Toxics Assessment (NATA), which is a comprehensive evaluation of air toxics in the US. This includes the expansion of air toxics monitoring, improvement and periodic updating of emission inventories, improvement of national- and local-scale modeling, continued research on health effects and exposures to both ambient and indoor air, and improvement of assessment tools.

NEPA - National Environmental Policy Act 
The National Environmental Policy Act (NEPA) is a United States environmental law that promotes the enhancement of the environment and established the President's Council on Environmental Quality (CEQ). The law was enacted on January 1, 1970. As the bill was an early step towards the development of the United States's environmental policy, NEPA is referred to as the “environmental Magna Carta”. NEPA's most significant outcome was the requirement that all executive federal agencies prepare environmental assessments (EAs) and environmental impact statements (EISs). These reports state the potential environmental effects of proposed federal agency actions. NEPA does not apply to the President, Congress, or the federal courts.

NESHAP - National Emission Standard for Hazardous Air Pollutants 
The FCAA requires EPA to regulation HAP from categories of industrial facilities. Like MACTs, the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) are emissions standards set by EPA. They may require one or more technologies or set emission limits for single or multiple HAPs. NESHAPS may apply only major facilities or to major and area (non-major) facilities. NESHAPs are authorized by Section 112 of the FCAA and the regulations are published in 40 CFR 63.

Netting is a term used to describe a process by which emissions from one source are reduced or traded for another in order to avoid a permitting action. The goal is to allow an increase in one location by implementing a reduction in another so that there is a zero sum.

NMHC - Nonmethane Hydrocarbons 
Nonmethane hydrocarbons (NMHC) are the total quantity of hydrocarbons in an exhaust sample minus the fraction of methane. Methane is usually determined using a separate sample and measured with gas chromatography or a flame ionized detector.

NMOC/NMOG - Nonmethand Organic Compounds/Gases 
As implied, Nonmethane Organic Compounds (NMOC) or Gases (NMOG) include all the organic compounds in an exhaust sample, except methane. Compounds that may be otherwise exempted as VOCs by regulation (such as ethane, acetone and oxygenated compounds) would be included.

NOX - Nitrogen Oxides 
Nitrogen oxides (NOX) is a generic term for the nitrogen oxide (NO) and nitrogen dioxide (NO2) compounds and their intermediaries. These chemicals are commonly produced from the reaction among nitrogen, oxygen and even hydrocarbons during combustion, but also occur naturally by lightning. NOX gases react to form smog and acid rain as well as being central to the formation of tropospheric ozone and is a criteria air pollutant. NOX should not be confused with nitrous oxide (N2O), which is a greenhouse gas and has many uses as an oxidizer, an anesthetic, and a food additive.

NOAA - National Oceanic and Atmospheric Administration 
The National Oceanic and Atmospheric Administration (NOAA) is a scientific agency within the US Department of Commerce focused on the conditions of the oceans and the atmosphere. NOAA warns of dangerous weather, charts seas, guides the use and protection of ocean and coastal resources, and conducts research to improve understanding and stewardship of the environment.

NOC - Notice of Construction 
Under WA State law, permits are requires fro certain facilities to emit air pollution into the public air. In order to do so, the facility must provide a Notice of Construction (NOC) application to the permitting agency. If the facility's proposal can be allowed without violating any air pollution regulations, an Order of Approval to Construct is issued and the facility can start construction. Note that in WA State, the NOC is a pre-construction permit and the Order of Approval is a construction and operating permit. SWCAA uses the terms ADP application and ADP as equivalent to NOC application and Order of Approval. The documents have the same legal standing.

NOV - Notice of Violation 
If a person (including a facility) is found to be violating an air permit, or air law, rule, or regulation, the agency responsible for enforcement of air pollution related matters may issue a Notice of Violation (NOV) to the person. The NOV is literally a notice that the agency asserts there is a violation of an air pollution regulation. An NOV is usually followed by either a Notice to Correct or a Notice of Penalty.

NSPS - New Source Performance Standards 
Under 40 CFR 60, EPA has promulgated a series of regulations that pertain to new facilities and processes. These regulations outline the requirements that apply to the facilities and processes and include the maximum emission levels (performance standards) allowed.

NSR - New Source Review 
In WA state, prior to constructing a new facility, a new process that emits air pollution, or modifying an existing process, a permit application (NOC or ADP application) must be filed with the permitting agency. The permitting agency must review the proposal to determine if the new construction or modification can proceed without violating any air pollution regulations. Although it also applies to modifications, this process is called New Source Review (NSR).

NTIS - National Technical Information Service 
The National Technical Information Service (NTIS) is an agency within the United States Department of Commerce. The primary mission of NTIS is to collect and organize scientific, technical, engineering, and business information generated by U.S. Government-sponsored research and development, for private industry, government, academia, and the public. The systems, equipment, financial structure, and specialized staff skills that NTIS maintains to undertake its primary mission allow it to provide assistance to other agencies requiring such specialized resources.


O & M - Operations and Maintenance Plan/Program 
An Operations and Maintenance (O&M) plan is a formulated program that defines training, cleaning, work practices, or other activities that ensure that equipment or processes are being operated properly or efficiently.

O3 - Ozone 
Ozone (O3) is an oxygen compound that is both naturally-occurring and man-made (as a secondary pollutant). O3 forms in the upper atmosphere due to ultraviolet radiation reacting with oxygen in the atmosphere and this "ozone layer" helps to protect the surface from the suns's radiation. However, at ground level, O3 forms due to chemical reactions between NOX and VOCs, mostly from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents. When inhaled, O3 can trigger a variety of health problems including chest pain, coughing, throat irritation, and airway inflammation. It also can reduce lung function and harm lung tissue and can worsen bronchitis, emphysema, and asthma, leading to increased medical care. O3 is a criteria air pollutant and is subject to a NAAQS.

OAQPS - Office of Air Quality Planning and Standards 
The Office of Air Quality Planning and Standards is an office at EPA whose primary mission is to preserve and improve air quality in the United States. To accomplish this, OAQPS compiles and reviews air pollution data, develops regulations to limit and reduce air pollution, assists states and local agencies with monitoring and controlling air pollution, makes information about air pollution available to the public, and reports to Congress the status of air pollution and the progress made in reducing it.

OAR - Office of Air and Radiation 
The Office of Air and Radiation (OAR) develops national programs, policies, and regulations for controlling air pollution and radiation exposure. OAR is concerned with pollution prevention and energy efficiency, indoor and outdoor air quality, industrial air pollution, pollution from vehicles and engines, radon, acid rain, stratospheric ozone depletion, climate change, and radiation protection. OAR is responsible for administering the FCAA, the Atomic Energy Act, the Waste Isolation Pilot Plant Land Withdrawal Act, and other applicable environmental laws.

OECA - Office of Enforcement and Compliance Assurance 
The Office of Enforcement and Compliance Assurance (OECA) goes after pollution problems that impact communities through vigorous civil and criminal enforcement. Enforcement activities target the most serious water, air and chemical hazards. As part of this mission, OECA works to advance environmental justice by protecting communities most vulnerable to pollution.


PAH - Polycyclic Aromatic Hydrocarbon 
Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned. PAHs generated from these sources can bind to or form small particles in the air. High-temperature cooking will form PAHs in meat and in other foods. PAHs are characterized by multiple combined benzene rings.

Pb - Lead 
Lead (chemical symbol Pb) is a soft metal element. Lead is used in building construction, lead-acid batteries, bullets and shot, weights, as part of solders, pewters, fusible alloys, and as a radiation shield. In the environment, lead and lead compounds are highly toxic to most organisms, regardless of whether the material is inhaled or ingested. Lead is a criteria pollutant and is subject to a NAAQS.

PCB/PBB - Polychlorinated/Poly Brominated Biphenyls 
Polychlorinated or polybrominated biphenyls (PCBs and PBBs) are a group of chemicals characterized by a diphenyl ring that is partially or fully saturated with chlorine or bromine, respectively. The common formula is C12H10−xClx or C12H10−xBrx, where x is the number of chlorine or bromine atoms; there are 209 configurations with 1 to 10 chlorine or bromine atoms. While most PCBs are known or suspected carcinogens, it is not known for certain if PBBs could cause cancer in human beings. It has been observed that they can lead to cancer in lab mice exposed to very high concentrations of PBBs; therefore, most PBBs are reasonably suspected to be carcinogens.

PCDD/PCDF - Polychlorinated Dibenzodioxin/Polychlorinated Dibenzofurans 
Polychlorinated dibenzodioxins (PCDDs) and Polychlorinated Dibenzofurans (PCDFs) are a group of polyhalogenated organic compounds that are significant environmental pollutants. Often classified as "dioxins", they occur as by-products in the manufacture of some organochlorides, in the incineration of chlorine-containing substances such as polyvinyl chloride (PVC), in the chlorine bleaching of paper, and from natural sources such as volcanoes and forest fires.

PLUVUE - Plume Visibility Model 
The Plume Visibility (PLUVUE) Model is a computer model used to calculate visual range reduction and atmospheric discoloration caused by plumes consisting of PM, NOX, and SOX emitted from emission sources.

PM - Particulate Matter 
Particulate Matter (PM) are microscopic solid or liquid matter suspended in the Earth's atmosphere. Sources of PM can be man-made or natural. They have impacts on climate and precipitation that adversely affect human health.

PM10 - Particulate Matter less than 10 microns in size 
PM10 is a subset of PM with particulates having an aerodynamic diameter of less than 10 µm. Typically, at this size, the particles may be inhaled, but do not penetrate deeply in to the lungs. PM10 is a criteria air pollutant and is subject to a NAAQS.

PM2.5 - Particulate Matter less than 2.5 microns in size 
PM2.5 is a subset of PM (and PM10) with particulates having an aerodynamic diameter of less than 2.5 µm. Typically, at this size, the particles may be inhaled and penetrate deeply into the lungs; there is some evidence that PM2.5 may enter the bloodstream through inhalation. PM2.5 may cause severe health effects. PM2.5 is a criteria air pollutant and is subject to a NAAQS.

POM - Polycyclic organic Matter 
The term Polycyclic Organic Mmatter (POM) defines a broad class of compounds that includes the PAHs, of which benzo[a]pyrene is a member. POM compounds are formed primarily from combustion and are present in the atmosphere in particulate form.

ppb - Parts per billion 
A unit representing 1 part in 1,000,000,000 or 10−9.

ppm - Parts per million 
A unit representing 1 part in 1,000,000 or 10−6.

PSD - Prevention of Significant Deterioration 
Prevention of Significant Deterioration (PSD) applies to new major sources or major modifications at existing sources for pollutants where the area the source is located is in attainment or unclassifiable with the NAAQS. It requires installation of the BACT, an air quality analysis, an additional impacts analysis, and public involvement. Facilities subject to PSD must have a maximum potential-to-emit of 250 tpy (100 tpy for specific categories) of criteria pollutants or 100,000 tpy of CO2e. PSD permits are issued by WA Department of Ecology or EFSEC.

PTE - Potential to Emit 
Potential-to-emit (PTE) is the maximum capacity of a stationary source to emit under it's physical and operational design. typically this is the maximum hourly operation multiplied by 8760 hr/yr. For example, given a boiler that produces 2 lb/hr of emissions, the PTE is 2 lb/hr times 8760 hr/yr or 8.76 ton/yr. In some circumstances this is a theoretical limit, but for some processes that have continuous operation, the actual emission may equal the PTE.


QA/QC - Quality Assurance/Quality Control 
Quality Assurance/Quality Control (QA/QC) is the combination of quality assurance, the process or set of processes used to measure and assure the quality of a measurement or product, and quality control, the process of ensuring that the measurement or product is within an expected range. In air quality, QA/QC is generally used to demonstrate that an instrument is measuring a quantity correctly and within a reasonable range of accuracy.


RACT - Reasonably Available Control Technology 
Reasonably available control technology (RACT), when applied to an emission unit or process, is the lowest emission limitation that a particular source is capable of meeting by application of control technology that is reasonably available considering technological and economic feasibility. The RACT standard is less stringent than either the BACT or LAER standards.

RICE - Reciprocating Internal Combustion Engine 
A stationary reciprocating internal combustion engine (RICE) is any internal combustion engine which uses reciprocating motion to convert heat energy from fuel into mechanical work. There are generally two types of RICEs, compression ignition, which runs on diesel and spark ignition, which runs on gasoline, propane or other gaseous fuel.

RVP - Reid Vapor Pressure 
Vapor pressure is a measure of the volatility of a material. For certain material, mostly petroleum products like gasoline, a modified version of vapor pressure, called the Reid Vapor Pressure (RVP) is used instead. When determining RVP, tests are usually performed using small sample sizes that may contain dissolved gases, which causes the RVP to differ somewhat from true vapor pressure.


SCC - Source Classification Code 
A Source Classification Code (SCC) is an 8-digit (minimum) code used to classify different types of emissions activities by a unique source category-specific process or function that emits an air pollutant. It is a hierarchical system in which the classification of the emissions process becomes increasingly more specific with each of the four levels (moving from left to right).

scfm - Standard Cubic Feet per Minute 
Standard cubic feet per minute (SCFM) is the volumetric flow rate of a gas corrected to "standardized" conditions of temperature and pressure thus representing a fixed number of moles of gas regardless of composition and actual flow conditions.

SEPA - State Environmental Policy Act 
Washington State has codified a State Environmental Policy Act (SEPA) under WAC 197-11 that is partially modeled after the federal NEPA. SEPA is a process by which a proposed project is evaluated against many environmental aspects, such as air, water waste, noise, light, traffic, and impacts to sensitive plants and animals. The SEPA Checklist may be used by other agencies to determine if there are impacts to media over which the agency has jurisdiction.

SIC - Standard Industrial Classification 
The Standard Industrial Classification (SIC) Code is a four-digit hierarchical numerical code used to identify business types, materials, commodities, and activities. It is typically used to provide a way to compare statistics between different business activities. It has generally been replaced by the more current NAICS code.

SIP - State Implementation Plan 
The State Implementation Plan (SIP) is the federally-enforceable plan for each State that identifies how that State will attain and/or maintain the NAAQS. Each State is required to have a SIP that contains the control measures and strategies developed through a public process, formally adopted by the State, and submitted by the Governor's designee to EPA (which EPA must formally act on) as revisions to their plan to attain and maintain the national ambient air quality standards.

SLAMS - State/Local Air Monitoring Station 
A State/Local Air Monitoring Station (SLAMS) is an air pollution monitor that measures ambient concentrations of those pollutants for which NAAQS have been established in 40 CFR Part 50. Information from the SLAMS is used to designate nonattainment and attainment areas.

SO2 - Sulfur Dioxide 
The largest source of SO2 in the atmosphere is the burning of fossil fuels by power plants and other industrial facilities. Smaller sources of SO2 emissions include: industrial processes such as extracting metal from ore; natural sources such as volcanoes; and locomotives, ships and other vehicles and heavy equipment that burn fuel with a high sulfur content. SO2 is a criteria air pollutant and is subject to a NAAQS.

SOX - Sulfur Oxides 
Sulfur oxides (SOX) is a general term that represents a group of sulfur-containing compounds. Sulfur dioxide (SO2) is the pollutant of greatest concern, although other compounds, such as SO3 are also found in the atmosphere. SOX can react with other compounds in the atmosphere to form small particulates, including PM2.5.

SQER - Small Quantity Emission Rate 
The small quantity emission rate (SQER) is an emission rate threshold, in lb/hour or lb/year, established under WAC 173-460 (toxic regulation for new sources). The SQER is established for specific pollutants and represents a threshold below which no adverse human health impacts are expected. The SQER is related to the ASIL, which is also a threshold for human health impacts under WAC 173-460.

STP - Standard Temperature and Pressure 
In air quality, Standard conditions are a temperature of 68°F and a pressure of 1 atm. Using the Ideal Gas Law, the actual temperature and pressure of an exhaust can be corrected to Standard conditions.

SWCAA - Southwest Clean Air Agency 
The Southwest Clean Air Agency (SWCAA) is an independent governmental agency, classified officially as a municipal corporation, and is responsible for enforcing federal, state and local outdoor air quality standards and regulations in Clark, Cowlitz, Lewis, Skamania and Wahkiakum counties of southwest Washington state. SWCAA was formed in 1967 and has the responsibility of regulating all outdoor air pollution sources within its five county jurisdiction, with the exception of automobiles, chemical paper and pulp mills, and aluminum reduction plants. SWCAA is governed by an eleven member Board of Directors, made up of a representative from each county commission, one city council member from the largest city within each county, and a representative at large.


TAP - Toxic Air Pollutant 
A toxic air pollutant (TAP) is an air contaminant that has been demonstrated to cause harm in humans, plants or animals. SWCAA operates under a version of WAC 173-460 that includes a list of chemicals and chemical groups that are considered toxic and that whose emissions are regulated to minimize the effect on the public's health. Those TAPs that are considered carcinogens are regulated to prevent more than 1 in 1,000,000 cancer cases in the general population.

THC - Total Hydrocarbons 
Total hydrocarbons (THC) are the total quantity of hydrocarbons in an exhaust sample, but would be less than TOC in the presence of oxygenated organic compounds, such as alcohols and acetone. Although often considered synonymous with VOC, this quantity often includes compounds that are not considered VOCs, such as methane and ethane.

TLV - Threshold Limit Value 
The threshold limit value (TLV) is a concentration limit recommended by the American Conference of Governmental Industrial Hygienists (ACGIH) for a normal 8-hour workday and 40-hour work week. Exceeding the TLV would represent adverse health effects to workers.

TOC - Total Organic Carbon 
Total organic carbon (TOC) represents all of the organic compounds in an exhaust stream. It would represent the maximum concntrations of organics being emitted, including compounds that may be exempted from regulation and compounds that contain elements other than carbon and hydrogen.

tpy - Tons Per Year 
The volume of air pollutants released in a year as expressed in tons.

TRS - Total Reduced Sulfur 
Total Reduced Sulfur (TRS) is the sum of the sulfur compounds hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide, and any other organic sulfides present expressed as hydrogen sulfide (H2S).

TSP - Total Suspended Particulates 
Particulate Matter (PM) are microscopic solid or liquid matter suspended in the Earth's atmosphere with an aerodynamic diameter generally less than 30 µm. Sources of PM can be man-made or natural. They have impacts on climate and precipitation that adversely affect human health.


UAM - Urban Airshed Model 
The Urban Airshed Model (UAM) is a three-dimensional, multi-scale photochemical grid model that calculates concentrations of pollutants by simulating the physical and chemical processes in the atmosphere. Because it accounts for spatial and temporal variations as well as differences in the reactivity of emissions, the UAM is useful for evaluating the air-quality effects of emission control scenarios.

UGA - Urban Growth Area 
Urban growth areas (UGA) or boundaries (UGB) are geographic areas defined in plans or regulations as desirable and appropriate for growth during a defined period of time, usually 20 years. Typically these are developed areas inside a county but outside a city limit into which a city expects to expand.

UST - Underground Storage Tank 
An underground storage tank (UST) is one or many tanks, including connected underground pipes, that are used to contain regulated substances. Typically, the volume of underground pipes is 10% or more beneath the surface of the ground.


VE - Visible Emissions 
Visible emissions (VE), also called opacity, are particulate or other material, generally emitted from a stack, that obscures a background when viewed through the emission plume. The density of the emission is related to the concentration of emissions. EPA Method 9 is a technique that is taught to industry and regulators that allows a numeric evaluation of the opacity level on a scale of 0 to 100 to be determined with the naked eye.

VMT - Vehicle Miles Traveled 
The number of miles a vehicle as traveled in a given time.

VOC - Volatile Organic Compounds 
VOC is defined by EPA as any compound of carbon that participates in atmospheric photochemical reactions. For aircraft, this is further defined as exhaust TOC corrected to exclude the mass of methane, ethane, and acetone and to fully account for the mass of formaldehyde and acetaldehyde. Notably, additional compounds are excluded/exempt from this group when sources other than aircraft engines are being considered. VOC also excludes carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate. While not specifically a criteria pollutant, VOCs are often included as a precursor to the formation of O3, which is a criteria pollutant.


YTD - Year to Date 
Items that are contained within the beginning of calendar or fiscal year to the present time. This may be a sum of values or a count of items.