Glossary of AQ Terms

Glossary of terms used when discussing air pollution:

Acid rain: precipitation that is more acidic than normal because it contains sulfuric acid and nitric acid derived from oxides of sulfur (SOx) and nitrogen (NOx) in the atmosphere. Acidity can also originate from atmospheric particulate matter (PM10).
Acute: immediate, brief, and severe - in reference to the duration of exposure or to the effects of pollutants, those effects-that follow exposure more or less immediately as a direct reaction to exposure.

Aerosol: a gas that contains suspended solid particles or droplets of liquid able to stay suspended in air because of their very small size (usually less than one micrometer in diameter).

Air pollutant: an airborne substance occurring in the ambient air which has potential to cause harm to human health or welfare or to plant and animal
life or materials.

Airshed: a geographical region with some sort of natural boundaries which demonstrates common production and exchange of air pollutants.

Alveoli: small air "sacks" deep in the lungs where exchange of carbon dioxide and oxygen occurs. Alveoli are delicate structures which are prone to damage from air pollutants.

Ambient air: outside air; the air around us.

Ambient air quality standard: federal limit for a pollutant in ambient air that serves as a target in local air quality improvement or protection programs. The primary standard protects public health; the secondary standard protects public welfare. The federal government establishes air quality standards, but more strict standards may be established by state governments.

Asthma: a respiratory disease characterized by the narrowing of the respiratory pathways and the excess production of mucus, shortness of breath, difficulty in breathing and coughing. Asthma is usually caused or aggravated by allergies and air pollution.

Biodegradable pollutant: a pollutant which can be detoxified in some manner in the environment. Detoxification can take from minutes to years.

Bronchitis: a lung disorder characterized by inflammation and irritation of bronchi (airways of the lower respiratory tract). Bronchitis appears to be caused and aggravated by smoking and air pollution.

Cancer: a group of diseases characterized by the uncontrollable growth of cells. These cells invade surrounding tissues, interrupting organ function and often causing death.

Carcinogen: a substance which causes cancer. Numerous chemical compounds common in polluted air and water are carcinogens.

Chronic: long-lasting or long-term in reference to either duration of exposure or effect of exposure to a pollutant. (Example: Exposure to even low levels
of ozone can result in permanent scaring of the lungs causing chronic lung disease.)

Concentration: the amount of a substance in a given volume of air, water or other medium. (Example: PM10 concentration is measured as the weight [micrograms] of small particles in a cubic meter of ambient air.)

Convection: the movement of air or water upward as a result of heating, which causes a decrease in the density in the air or water and makes it rise. Convection currents in air tend to disperse air pollutants as the pollutants are carried
up and away from the surface of the earth.

Electrostatic precipitator: a pollution control device for removing particulate matter. Precipitators work by creating an electrical charge on the particles and then attracting them to plates with the opposite charge. Particulate matter is then
cleaned off of the plates.

Emission: discharge of a pollutant from some source into the environment.

Emission standard: limit in the amount of a pollutant that can be legally discharged into the environment from a particular source. Under the Clean Air Act of 1970, emissions from existing sources are controlled by the states under State Implementation Plans (SlP) approved by the EPA. The federal government retained control over new sources, establishing maximum emission standards for any new plants built in any state.

Environmental Protection Agency (EPA): the federal agency charged with the enforcement of all federal regulations having to do with environmental pollutants. The address is 401 M Street N.W., Washington, DC 20460.

Epidemiology: an investigative approach to disease that looks for the factors that account for the frequency and patterns of disease within defined populations.

Fly ash: gas-borne solid particles resulting from the combustion of fuel and other materials.

Hazardous waste: any substance discarded into the air or water or onto the land which poses a hazard to human health or welfare or to the environment.

Industrial smog: pollution produced by industries composed mostly of particulate matter and sulfur oxides produced primarily by the burning of coal and oil. Industrial smog is characterized by a brown haze (as compared to photochemical smog which tends to be gray).

Infectious disease: a disease caused by agents including bacteria, viruses or parasitic worms. Since air pollution negatively impacts the immune system, the incidence of infectious diseases increases with increased air pollution.

Internal costs: costs of production that are directly borne by the producer or consumer of a product. These costs exclude external costs such as pollution, environmental damage and nuisance and aesthetic degradation to the surrounding
community.

Mutagen: anything capable of increasing the rate of genetic mutation in living organisms. Radioactive substances and many chemicals commonly found in air pollution are important mutagens.

Nonbiodegradable pollutant: a pollutant which retains its toxicity for extremely long periods of time. Some lead and mercury compounds and radioactive substances are nonbiodegradable pollutants.

Noninfectious disease: an illness not caused by a disease-causing organism or virus. Examples include heart disease, bronchitis, some cancers and asthma. Unlike infectious diseases, when air pollution indirectly influences the incidence of disease, air pollution is actually the causal agent of some non-infectious diseases.

Ozone: a gas (O2) resulting from complex chemical reactions in the atmosphere between hydrocarbons, nitrogen oxides and sunlight. Ozone in the lower atmosphere is a dangerous pollutant. In the upper atmosphere, ozone is important in filtering out ultraviolet radiation, thus protecting against such human ailments as
skin cancer and cataracts.

PANs (peroxeyl nitrates): important components of photochemical smog formed from the reaction of hydrocarbons, nitrogen oxides and sunlight. PANs are strong oxidants and can have a significant negative impact upon human health.

Particulate: a small particle of solid matter or a droplet of liquid of a size that allows it to remain suspended in air.

Parts per billion (ppb): the number of parts of a given substance in a billion parts of some other substance. (Example: In the ambient air, 1 ppb lead represents one part of lead per 1 billion parts of air.)

Parts per million (ppm): the number of parts of a given substance in a million parts of some other substance. (Example: In the ambient air, 1 ppm lead represents one part of lead per 1 million parts of air.)

PM10: fine particulate matter suspended in the atmosphere. PM10 particles have a diameter of less than 10 micrometers.

Photochemical reaction: a chemical reaction that is activated by sunlight. Photochemical reactions are common in the formation of secondary air
pollutants.

Photochemical smog: collection of harmful materials in the air resulting from the action of sunlight on nitrogen oxides, hydrocarbons, and other chemicals in the air. Photochemical smog generally develops in cites with warm climates or during summer months.

Pollutant Standard Index (PSI): a calculation by formula of the degree to which air quality relates to the standards set by the EPA for each of the major pollutants.

Pollution: the addition of an undesirable substance to the air, water or soil that in some manner damages the biological, structural or aesthetic value of the ecosystem. Pollution often effects the health and welfare of humans.

Primary air pollutant: an air pollutant that is released directly by a pollution emission source. Primary pollutants are differentiated from secondary pollutants which form chemically in the atmosphere by the reaction of primary pollutants.

Risk assessment: the process of determining the adverse consequences of some technology or process to the individual and/or the society. Risk assessment must deal with both short-term and long-term risks.

Scrubber: a pollution control device that sprays a stream of water across or through a stream of polluted air to remove pollutants. Scrubbers are widely used in a variety of combustion processes.

Secondary air pollutant: an air pollutant that forms in the atmosphere by chemical reactions. Secondary pollutants are not released as emissions by pollution sources. It is difficult to obtain accurate estimates concerning the number of secondary air pollutants. Some experts put the number at around 30,000.

Smog: a term that combines the words "smoke" and "fog," coined originally in Los Angeles to characterize a visible combination of smoke and fog. Photochemical smog is the result of the interaction between nitrogen oxides and hydrocarbons
under the influence of sunlight.

Synergism: an interaction in which the total effect of the interaction is greater than the sum of the two taken separately. Air pollutants often create a synergistic effect on human health.

Synfuels: synthetic gaseous and liquid fuels synthesized from coal or other sources.

Thermal inversion: an atmospheric meteorological condition in which a layer of warm air acts like a lid to trap a layer of cold air beneath it. This frustrates the normal convection of air upward as the surface of the earth is heated. Air
pollution levels often reach very high levels during periods of thermal inversion.

TSP (total suspended particulates): suspended particulate matter of variable size. TSP was formerly regulated by the EPA. Recent studies have indicated however, that fine particulate matter (PM2.5) has the strongest negative impact on
human health. Thus, the EPA now regulates PM10 and PM 2.5, rather than TSP.

Urban heat island (urban inversion): a situation functionally similar to a natural thermal inversion. Human activities in urban areas often create a warm "island" of air that can trap air pollutants.


Glossary terms provided by:

Utah County Clean Air Coalition • P.O. Box 1342 • Orem, UT 84059-1342

Air Permitting and Clean Air Act Related Acronyms:

ACGIH American Conference of Governmental Industrial Hygienists

AIRS Aerometric Information Rertrieval System

AP-42 Compilation of Air Pollutant Emission Factors

API American Paper Institute/American Petroleum Institute

AQCR Air Quality Control Region

ASTM American Society for Testing & Materials

AWMA Air & Waste Management Assocation

BACT Best Available Control Technology

BDT Best Demonstrated Technology

BID Background Information Documents

BIF Boilers and Indutrial Furnaces (EPA's)

CAA Clean Air Act

CAAA Clean Air Act Amendments

CAS Chemical Abstract Service

CEM Continuous Emissions Monitoring

CEMS Continuous Emissions Monitoring Sytems

CERCLA Comprehinsive Environmental Responsbility, Compensation and Liability Act

CFC Chloroflorocarbon

CFR Code of Fedral Regulations

CMA Chemical manufactures Assocation

CTG Control Technique Guideline CAA Section 183

DOE Departmet of Energy

DOJ Department of Justice

DOT Department of Transportaion

DSCF Dry Standard Cubic Feet (or Foot)

DSCM Dry Standard Cubic Meters

EA Environmental Assessment

EI Emissions Inventory

EIS Emissions Inventory Statement

EPA Environmental Protection Agency

EPCRA Emergecy Planning and Community Right-to-Know Ac

ESP Electrostatic Precipitator

FGR Flue Gas Recirculation

FIP Federal Implementaion Plan

FR Federal Register

GACT Generally Available Control Techology

GAQM Guideline on Air Quality Models

GEP Good Engineering Practice

GIS Geographic Information System

HAP Hazardous Air Pollutant

HHV Higher Heating Volume

HON Hazardous Organic NESHAP (see NESHAP below)

IDLH Immediate Danger to Life& Health

ISCLT Indutrial Source Complex Long-Term Model

ISCST Industrial Source Complex Short-Term Model

LAER Lowest Achievable Emission Rate

LHV Low Heating Value

MACT Maximum Achievable Emission Rate

MMBtu Million British Thermal Units

MPTER Multiple Point Gaussion Dispersion Algorithm with Terrain Adjustment

MSDS Material Safety Data Sheet

MSW Municipal Solid Waste

MWC Municipal Waste Combuster

NA Nonattainment

NAAQS Natioanal Ambient Air Quality Standards Title I

NADP National Atmospheric Deposition Program

NAPAP Natioanl Acid Precipitation Assessment Program

NCASI Natioanl Council of the Paper Industry for Air and Stream Improvment

NESHAPs National Emissions Standards for Hazardous Air Pollutants

NOV Notice of Violation

NPDES National Pollutant Discharge Elimination System

NSPS New Source Performance Standard

NSR New Source Review

OAQPS Office of Air Quality Planning and Studies

OMB Office of Management and Budget

OSHA Occuaptional Safety &Health Administration

PSD Prevetion of Significant Deterioration

PTE Potential to Emit

RACT Reasonably Available Control Technology

RCRA Resource Conservation and Control Act

RDF Refuse Derived Fuel

RFP Reasonable Further Progress/Request for Proposal

ROM Regional Oxidant Model

SCAQMD South Coast Air Quality Management (in California)

SCC Souce Classification Code

SCR Selective Catalytic Reduction

SIC Standard Industrial Classification

SIP State Implementaion Plan

SNCR Selective Non-Catalytic Reduction

SOCMI Synthetic Organic Chemical Manufacuring Industry

TLV Health Threshold Limit Value

TRI Toxic Release Inventory

TRIS Toxic Release Information System

TSCA Toxic Substances Control Act

UAM Urban Airshed Model

USC United States Code

USGS U.S. Geological Survey

UTM Universal Transverse Mercator

Provided By : Trinity Consltants12801 North Central Expressway

Suite 1200 Dallas, Texas 75243