San Joaquin Valley Unified Air Pollution Control District April 30, 2007

Acronyms and Glossary 

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Glossary-1 

Acronyms and Glossary 

ACRONYMS, ABBREVIATIONS, AND INITIALISMS 

AERO: Advanced Emissions Reductions Options 

A.I.R: Agriculture Improving Resources 

APCO: Air Pollution Control Officer 

AQGGP: Air Quality Guidelines for General Plans 

AQI: Air Quality Index 

ARB: California Air Resources Board 

BAAQMD: Bay Area Air Quality Management District 

BACT: Best Available Control Technologies 

CAA: Clean Air Act 

CAFO: confined animal facility operations 

CalTrans: California Department of Transportation 

CAMx: Comprehensive Air Quality Model with Extensions 

CART: Center for Advanced Research and Technology 

CEM: Continuous Emission Monitoring 

CEQA: California Environmental Quality Act 

CCOS: Central California Ozone Study 

CMP: Conservation Management Practices 

CO: carbon monoxide 

CRPAQS: California Regional Particulate Air Quality Study 

DMV: Department of Motor Vehicles 

DPAG: Dairy Permitting Advisory Group 

District: San Joaquin Valley Air Pollution Control District 

DPR: Department of Pesticide Regulation (DPR) 

EPA: U.S. Environmental Protection Agency 

EJ: environmental justice 

ERC: emission reduction credits 

FR: Federal Register 

GAMAQI: Guide for Assessing and Mitigating Air Quality Impacts 

Heavy-Duty Program: Heavy-Duty Engine Emission Reduction Incentive Program 

IC: internal combustion 

ISR: Indirect Source Review 

ISSRC: International Sustainable Systems Research Center 

MM5: Mesoscale Model version 5 

NAAQS: National Ambient Air Quality Standards 

NOx: oxides of nitrogen 

OADP: Ozone Attainment Demonstration Plan (for 1-hour ozone) 

PM: particulate matter 

PM2.5: particulate matter 2.5 microns or less in diameter 

PM10: particulate matter 10 microns or less in diameter 
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Ppm: parts per million 

PSA: Public Service Announcements 

PSI: Pollutant Standards Index (now the AQI) 

RACT: reasonably available control technology 

REMOVE : Reduce Motor Vehicle Emissions 

RFP: reasonable further progress 

ROP: rate of progress (for 1-hour ozone) 

RRF: relative reduction factor 

SAPRC: [California] Statewide Air Pollution Research Center 

SIP: state implementation plan 

SJVAB: San Joaquin Valley Air Basin 

SOx: oxides of sulfur 

TOG: total organic gases 

TPA: Transportation Planning Agencies 

TSP: total suspended particles 

VOC: volatile organic compounds 
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GLOSSARY 

Air Basin: An area of the state designated by the ARB pursuant to Subdivision (a) of 

Section 39606 of the CH&SC that has similar meteorological and geographic 

conditions. 

Air Monitoring: The periodic or continuous sampling and analysis of air pollutants in 

ambient air or from individual pollutant sources. 

Air Pollutants: Substances which are foreign to the atmosphere or are present in the 

natural atmosphere to the extent that they may result in adverse effects on 

humans, animals, vegetation, and/or materials. 

Air Pollution Control District (APCD): A county agency with authority to regulate 

sources of air pollution, other than emissions from mobile sources, such as 

refineries, manufacturing facilities, and power plants within a given county, and 

governed by a District Air Pollution Control Board composed of elected county 

supervisors. (Compare AQMD and Unified District) 

Air Pollution Control Officer (APCO): A person appointed by the APCB given the 

authority to appoint district personnel for the purpose of observing and enforcing 

the provisions of Part 4, Division 26 of the CH&SC. 

Air Quality Attainment Plan (AQAP): An air quality plan prepared in approximately 

1991 by each air pollution control district in the California that at that time was 

classified as nonattainment for specific state ambient air quality standards. 

Air Quality Management District (AQMD): A group of counties or portions of counties 

with authority to regulate sources of air pollution within the region and governed 

by a regional air pollution control board comprised mostly of elected officials from 

within the region. An AQMD is established by state legislation. (Compare APCD 

and Unified District). 

Ambient Air: Air occurring at a particular time and place outside of structures. Often 

used interchangeably with outdoor air. 

Anthropogenic: Of, relating to, or influenced by the impact of humans on nature; manmade. 

Area-wide Sources: Also known as "area" sources, are those sources which are not 

large enough to be tracked individually, but when added together can represent a 

large quantity of pollution. Examples of these sources include multiple stationary 

emission sources such as water heaters, gas furnaces, fireplaces, gas stations, 

dry cleaners and woodstoves. Area sources of pollution are identified by 

Category of Emission Source (CES) codes. 
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Attainment: Achieving and maintaining the air quality standards for a given 

 standard. 

Attainment Area: A geographic area that is in compliance with the National and/or 

California Ambient Air Quality Standards (NAAQS or CAAQS). 

Best Available Control Technology (BACT): The most up to date methods, systems, 

techniques, and production processes available to achieve the greatest feasible 

emission reductions for given regulated air pollutants and processes. BACT is a 

requirement of NSR (New Source Review) and PSD (Prevention of Significant 

Deterioration). 

Best Available Control Measure (BACM): A term used to describe the “best” 

measures (according to EPA guidance) for controlling small or dispersed sources 

of particulate matter and other emissions from sources such as roadway dust, 

woodstoves, and open burning. 

Best Available Retrofit Control Technology (BARCT): An emission limitation that is 

based on the maximum degree of reduction achievable, taking into account 

environmental, energy, and economic impacts by each class or category of 

source (Section 40406 CH&SC). 

Biogenic: Produced by living organisms. Biogenic emissions are of extreme interest 

because of the predominance of agriculture in the San Joaquin Valley; however, 

the District has no authority to regulate biogenic emissions. Preliminary studies 

indicate that biogenic emissions may be at least two times the total hydrocarbon 

emissions already quantified in the emissions inventory (in the AQAP). 

Bureau of Automotive Repair (BAR): An agency of the California Department of 

Consumer Affairs responsible for the implementation of the motor vehicle 

inspection and maintenance program (smog check). 

California Air Resources Board (ARB): The State's lead air quality agency consisting 

of an eleven-member Governor-appointed board and supporting staff fully 

responsible for motor vehicle pollution control, and having oversight authority 

over California's air pollution management program. 

California Environmental Quality Act (CEQA): A California law that sets forth a 

process for public agencies to make informed decisions on discretionary project 

approvals. The process aids decision makers to determine whether any 

environmental impacts are associated with a proposed project. It requires the 

elimination or reduction of environmental impacts associated with a proposed 

project and the implementation of mitigation measures to reduce or remove those 

impacts. 
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Carbon Monoxide (CO): A colorless, odorless gas resulting from the incomplete 

combustion of fossil fuels. Over 80 percent of the 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. 

Central California Ozone Study (CCOS): A research effort undertaken in 2001 to 

collect observations related to formation of ozone at the surface and aloft for a 

large area of central California, with supporting collection of activity and 

emissions data, to be followed by analysis and modeling. 

Conformity: A demonstration of whether a federally-supported activity is consistent 

with the State Implementation Plan (SIP) – per section 176(c) of the FCAA. 

Transportation conformity refers to plans, programs, and projects approved or 

funded by the Federal Highway Administration or the Federal Transit 

Administration. General conformity refers to projects approved or funded by 

other federal agencies. 

Consumer Products: Products such as detergents, cleaning compounds, polishes, 

personal care products, and automotive specialty products which are part of our 

everyday lives and, through consumer use, may produce air emissions which 

contribute to air pollution. 

Criteria Air Pollutant: An air pollutant for which acceptable levels of exposure can be 

determined and for which an federal or state ambient air quality standard has 

been set. Examples include: Ozone, Carbon Monoxide, Lead, Nitrogen Dioxide, 

Sulfur Dioxide, and PM10. 

Department of Motor Vehicles (DMV): The agency responsible for registering drivers 

and vehicles as well as collecting state and local motor vehicle fees. 

Design Value: The pollutant concentration used by air quality managers as the basis 

for determining attainment of an air quality standard, generally by using an air 

quality model. The design value may or may not be the same as the designation 

value. 

District Source: Any source for which the District has legal authority to set emissions 

standard and regulate the operations thereof. 

Emission Factor: For stationary sources, the relationship between the amount of 

pollution produced and the amount of raw material processed or burned. For 

mobile sources, the relationship between the amount of pollution produced and 

the number of vehicle miles traveled. By using the emission factor of a pollutant 

and specific data regarding quantities of material used by a given source, it is 

possible to compute emissions for the source. 
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Emission Inventory: An estimate of the amount of pollutants emitted into the 

atmosphere from major mobile, stationary, area-wide, and natural source 

categories over a specific period of time such as a day or a year. 

Emission Offset: Actual enforceable emission reductions from existing sources 

sufficient to offset anticipated emission increases associated with new or 

modified stationary sources. A rule-making concept whereby approval of a new 

stationary source of air pollution or increase of emissions from an existing source 

of air pollution is conditional on the equal or greater reduction of emissions from 

other existing stationary sources of air pollution. This concept is utilized in 

addition to reduction in emissions by employing BACT. 

Emission Projecting: Utilizing information and growth and control estimates to 

approximate future emissions. 

Emission Reduction Credit (ERC): Credits given for actual emission reductions that 

are real, enforceable, permanent, quantifiable, and surplus (beyond the required 

reduction). An actual credit is certified via a District-issued document that 

specifies the date of issuance, expiration date of credit, type of pollutant, and 

legal owner of emission reduction credits. In some cases, ERCs can be 

transferred to another owner or banked for future use. 

Emission Standard: The maximum amount or rate of a pollutant permitted to be 

discharged from a polluting source such as an automobile or smoke stack. 

Emissions Inventory: An estimate of the quantity of pollutants emitted into the 

atmosphere over a specific period such as a day or a year. Considerations that 

go into the inventory include type and location of sources, the processes 

involved, and the level of activity. 

Environmental Protection Agency (EPA): The United States Environmental 

Protection Agency is a federal agency charged with protecting human health and 

safeguarding the natural environment—air, water, and land-- upon which life 

depends. EPA promulgates national ambient air quality standards and 

implements other federal programs designed to improve air quality. 

Exceedance: An air pollutant that is monitored to be above the state and/or federal 

ambient air quality standard for that pollutant. 

Federal Clean Air Act (FCAA): A federal law passed in 1970 and significantly 

amended in 1977 and 1990 that forms the basis for the national air pollution 

control efforts. Basic elements of the Act include national ambient air quality 

standards for major air pollutants, air toxics standards, acid rain control 

measures, and enforcement provisions. 
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Federal Clean Air Act Amendments of 1990: The 1990 amended version of the 

federal CAA that mandates attainment of the National Ambient Air Quality 

Standards (NAAQS) by specified dates for nonattainment areas. Ozone 

nonattainment areas are sorted into categories (marginal, moderate, serious, 

severe, and extreme) with deadlines established ranging from three years for 

marginal areas to twenty years for extreme areas. 

Federal Implementation Plan (FIP): In the absence of an approved State 

Implementation Plan (SIP), a plan prepared by the EPA which provides 

measures that nonattainment areas must take to meet the requirements of the 

federal CAA. 

Federal Motor Vehicle Control Program (FMVCP): This program establishes the 

tailpipe emissions standards that are implemented by the Federal Government. 

Federal Source: Any source for which the United States government has legal 

authority to set emissions standards and regulate the operations thereof. The 

District does not have legal authority to set emissions standards for these 

sources, but may have authority to regulate their operations, or the makeup of 

the vehicle fleet. One example is US Postal Service fleets. 

Hydrocarbon (HC): any of a large number of compounds containing various 

combinations of hydrogen and carbon atoms. They may be emitted into the air 

as a result of fossil fuel combustion and fuel volatilization, and are a major 

contributor to smog. 

Indirect Source: Any facility, building, structure, or installation, or combination thereof, 

which generates or attracts mobile source activity that results in emissions of any 

pollutant (or precursor) for which there is a state or federal ambient air quality 

standard. Examples of indirect sources include employment sites, shopping 

centers, sports facilities, housing developments, airports, educational institutions, 

commercial and industrial developments, and parking lots and garages.

Indirect Source Review (ISR): A rule or regulation that governs entities such as 

stationary facilities, buildings, structures, properties, and/or roads which, through 

their construction to operation indirectly contributes to air pollution. This includes 

projects and facilities that attract or generate mobile sources activity (autos and 

trucks) such as employment sites, shopping centers, sports facilities, housing 

developments, airports, educational institutions, commercial and industrial 

developments, and parking lots and garages, that results in the emissions of any 

regulated pollutant. 

Inspection and Maintenance Program (I & M): A motor vehicle inspection program 

implemented by the Bureau of Automotive Repair. It is designed to identify 

vehicles in need of maintenance and to assure the effectiveness of their emission 

control systems on a biennial basis. The program was enacted in 1979 and 
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strengthened in 1990. The standard program is called Basic I & M. Enhanced I 

& M has more stringent testing requirements and is to be implemented in 

urbanized areas that are classified as "serious" and above nonattainment for 

ozone or "high moderate" and above for carbon monoxide and which had a 

population of 200,000 or more in 1980. Also known as a "smog check". 

Internal Combustion Engine (IC): A heat engine in which the combustion generates 

the heat inside the engine proper instead of in a furnace. An example of an IC 

engine is an automobile engine.

Inversion: A layer of warm air in the atmosphere that lies over a layer of cooler air, 

trapping pollutants. 

Local Source: Any source for which local governments (cities and counties) have 

primary regulatory authority. One example is land use decisions. The District 

does not have the legal authority to make land use decisions, which, per state 

law, are under the purview of cities and counties. The District does have 

authority, however, to control emissions from land use projects through its 

Indirect Source Review program. Additionally, the District submits comments on 

land-use proposals received from cities, counties, and other agencies under the 

California Environmental Quality Act (CEQA). The District also advises cities and 

counties regarding air quality issues in their general plans. Section 65302.1 of 

California Government Code requires cities and counties in the San Joaquin 

Valley to amend appropriate elements of their general plans to include data, 

analysis, comprehensive goals, policies, and feasible implementation strategies 

to improve air quality in their next housing element revisions. Cities and counties 

are required to submit these air quality amendments to the District for comment 

at least 45 days before adoption. 

Memorandum of Understanding (MOU): An agreement made among agencies for 

the purposes of jointly accomplishing a goal, program, etc. The governing 

boards of the involved agencies must ratify this agreement. 

Mobile Sources: Sources of air pollution that are not stationary by nature, such as 

automobiles, motorcycles, trucks, off-road vehicles, boats, and airplanes. 

National Ambient Air Quality Standards (NAAQS): Standards set by the EPA for the 

maximum levels of air pollutants that can exist in the ambient air without 

unacceptable effects on human health or the public welfare. 

New Source Review (NSR): The mechanism to assure that new and modified 

stationary sources will not interfere with the attainment or maintenance of any 

ambient air quality standard, or prevent reasonable further progress towards the 

attainment or maintenance of any ambient air quality standard. A program used 

in a non-attainment area to permit or site new industrial facilities or modifications 

to existing industrial facilities that emit non-attainment criteria air pollutants. The 
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two major requirements of NSR are Best Available Control Technology and 

Offsets. 

Nonattainment Area: An area identified by the EPA and/or ARB as not meeting either 

NAAQS or CAAQS standards for a given pollutant. 

Oxides of Nitrogen (NOx): A general term pertaining to compounds of nitric oxide 

(NO), nitrogen dioxide (NO2), and other oxides of nitrogen. Nitrogen oxides are 

typically created during combustion processes and are major contributors to 

smog formation and acid deposition. NO2 is a criteria pollutant, and may result in 

numerous adverse health effects. 

Ozone (O3): A reactive gas consisting of three oxygen atoms. In the troposphere, it is a 

product of the photochemical process involving the sun's energy. It is a 

secondary pollutant that is formed when nitrogen oxides (NOx) and volatile 

organic compounds (VOC) react in the presence of sunlight. Ozone at the 

earth's surface causes numerous adverse health effects and is a criteria 

pollutant. It is a major component of smog. In the stratosphere, ozone exists 

naturally and shields Earth from harmful incoming ultraviolet radiation. 

Ozone Attainment Demonstration Plan (OADP): A plan prepared by air pollution 

control districts and air quality management districts that proposes and 

evaluates, through modeling, emission controls deemed necessary to attain 

ambient air quality standards for 1-hour ozone. 

Ozone Precursors: Chemicals such as volatile organic compounds and nitrogen 

oxides, occurring either naturally or as a result of human activities, which 

contribute to the formation of ozone, a major component of smog. They are 

emitted directly from sources into the atmosphere. 

Particulate Matter (PM10): 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 the 

air sacs deep in the lungs where they may be deposited to result in adverse 

health effects. PM10 also causes visibility reduction and is a criteria air pollutant. 

parts per hundred million (pphm): Standard of measurement of concentration by 

which ozone or other atmospheric gases may be measured. One pphm is equal 

to ten ppb. 

parts per million (ppm): Standard of measurement of concentration by which ozone 

or other atmospheric gases may be measured. One ppm is equal to 100 pphm 

or 1000 ppb. 
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Photochemical Reaction: A term referring to chemical reactions brought about by the 

light energy of the sun. Photochemical reactions create harmful air pollutants 

such as ozone. 

Public Workshop: A workshop held by an air district for the purpose of informing the 

public and obtaining its input on the development of a regulatory action or control 

measure by that agency. 

Rate of Progress (ROP): The Federal Clean Air Act Amendments [Section 182(c)(2)] 

require ozone nonattainment areas designated as “serious” or above to 

demonstrate post-1996 volatile organic compound emission reductions of three 

percent per year, averaged over a 3-year period. The U.S. Environmental 

Protection Agency refers to these reductions as the rate-of-progress requirement. 

Reactive Organic Gas (ROG): A reactive chemical gas, composed of hydrocarbon 

compounds that may contribute to the formation of smog by their involvement in 

atmospheric chemical reactions. Also sometimes referred to as Non-Methane 

Organic Compounds (NMOCs). VOC emissions are a subset of ROG emissions. 

Regional Transportation Planning Agencies (RTPAs): The eight governmental 

bodies in the San Joaquin Valley primarily responsible for transportation planning 

in compliance with federal and state requirements. Also referred to as Valley 

Transportation Planning Agencies (TPAs). 

Reasonably Available Control Technology (RACT): Devices, systems, process 

modifications, or other apparatus or techniques that are reasonably available 

taking into account the necessity of imposing such controls in order to attain and 

maintain a national ambient air quality standard; the social, environmental, and 

economic impact of such controls; and alternative means of providing for 

attainment and maintenance of such standard. 

Reid Vapor Pressure (RVP): The absolute vapor pressure of volatile crude oil and 

volatile nonviscous petroleum liquids, except liquefied petroleum gases. 

San Joaquin Valley Air Basin (SJVAB): An air basin established by ARB that has 

similar meteorological and geographical conditions that consist of all of San 

Joaquin, Stanislaus, Merced, Madera, Fresno, Kings, and Tulare Counties, and 

the Valley portion of Kern County. 

San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD or District):

Also known as the "Valley Air District". The eight member counties include 

Fresno, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare Counties, 

and the Valley portions of Kern County. 

Smog: A combination of smoke, ozone, hydrocarbons, nitrogen oxides, and other 

chemically reactive compounds, which, under various conditions of weather and 
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sunlight, may result in a murky brown haze that causes adverse health effects. A 

primary source of smog is automobiles. 

Smog Check Program: A motor vehicle inspection program implemented by the 

Bureau of Automotive Repair. It is designed to identify vehicles in need of 

maintenance and to assure the effectiveness of their emission control systems 

on a biennial basis. The program was enacted in 1979 and strengthened in 

1990. Also known as the Inspection and Maintenance Program (I & M). 

State Implementation Plan (SIP): A document prepared by each state describing 

existing air quality conditions and measures which will be taken to attain and 

maintain national ambient air quality standards. 

State Source: Any source for which the State of California has legal authority to set 

emissions standards and regulate the operations thereof. The District does not 

have legal authority to set emissions standards for these sources, but may have 

authority to regulate their operations, or the makeup of the vehicle fleet. 

Examples include school bus fleets and other state vehicles. 

Stationary Sources: Non-mobile sources such as power plants, refineries, and 

manufacturing facilities that emit air pollutants. 

Transportation Control Measure (TCM): Any control measure to reduce vehicle trips, 

vehicle use, vehicle miles traveled, vehicle idling, or traffic congestion for the 

purpose of reducing motor vehicle emissions. TCMs can include encouraging 

the use of carpools and mass transit. 

Transportation Planning Agency (TPA): See Regional Transportation Planning 

Agency. 

Unified Air Pollution Control District: A specialized APCD in which two or more 

contiguous counties merge their county districts into one. A unified district is 

formed by action of the member counties. The San Joaquin Valley Unified Air 

Pollution Control District is a Unified District pursuant to Division 26, Part 3, 

Chapter 11 of the CH&SC. (Compare APCD and AQMD) 

United States Environmental Protection Agency (EPA): The United States agency 

charged with setting policy and guidelines, and carrying out legal mandates for 

the protection of national interests in environmental resources. 

Valley: All references to the "Valley" in this plan refer to the San Joaquin Valley. 

Valley Transportation Planning Agencies (TPAs): The eight governmental bodies in 

the San Joaquin Valley primarily responsible for transportation planning in 

compliance with federal and state requirements. Also referred to as Regional 

Transportation Planning Agencies (RTPAs). 
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Vehicle Miles Traveled (VMT): A measure of both the volume and extent of motor 

vehicle operation; the total number of vehicle miles traveled within a specified 

geographical area over a given period of time. 

Volatile Organic Compounds (VOC): Hydrocarbon compounds that exist in the 

ambient air. VOCs contribute to the formation of smog and/or may themselves 

be toxic. VOC emissions are a major precursor to the formation of ozone. VOCs 

often have an odor, and some examples include gasoline, alcohol, and the 

solvents used in paints.