Blackshare Environmental Solutions: A

A
Angstrom (1E-10 meters)

AA
Atomic Absorption: Refers to instrument for metals analysis

AA
Attainment Area (CAA)

AAC
Acceptable Ambient Concentration

AAPCO
Association of American Pesticide Control Officials, Inc.

AAR
Association of American Railroads

AAQS
Ambient Air Quality Standards (CAA)

Absorption
Penetration of a substance into the body of another

ACBM
Asbestos Containing Building Materials

ACL
Alternative Concentration Limit (40 CFR Part 403): General pretreatment regulations for existing and new sources of pollution (CWA)

ACM
Asbestos Containing Materials: Materials which contain greater than one percent asbestos

ACS
American Chemical Society

Act of God
An unanticipated grave natural disaster or other natural phenomenon (such as a tornado, earthquake, etc.), in which the effects of which could not have been prevented or avoided by the exercise of due care or foresight.

Acute Effect
An adverse effect on humans or animals, after a single significant exposure (e.g.) cyanide gas.

Acutely Hazardous Waste
Any EPA-RCRA hazardous waste beginning with the letter "P" (40 CFR 261.33 (e)) that by definition, is a commercial chemical product (non-process waste) and an off-specification commercial chemical product with only one active ingredient or any of the following "F" waste codes: F020, F021, F022, F023, F026, (40CFR 261.31).

A
Angstrom (1E-10 meters).

AA
Atomic Absorption: Refers to instrument for metals analysis.

AA
Attainment Area (CAA).

AAC
Acceptable Ambient Concentration.

AAPCO
Association of American Pesticide Control Officials, Inc.

AAR
Association of American Railroads

AAQS
Ambient Air Quality Standards (CAA).

Absorption
Penetration of a substance into the body of another.

ACBM
Asbestos Containing Building Materials.

ACL
Alternative Concentration Limit (40 CFR Part 403): General pretreatment regulations for existing and new sources of pollution (CWA).

ACM
Asbestos Containing Materials: Materials which contain greater than one percent asbestos.

ACS
American Chemical Society

acfm
Actual Cubic Feet per Minute of gas or air flowing at existing temperature and pressure.

ACGIH
American Conference of Governmental & Industrial Hygienists.

Acid
A hydrogen containing compound that reacts with water to produce hydrogen ions (H+) with a pH of less than 7.0.

Acid Rain
Acid rain is a form of air pollution produced when acid chemicals are incorporated into rain, snow, fog or mist. The "acid" in acid rain comes from sulfur oxides and nitrogen oxides, products of burning coal and other fuels and from certain industrial processes. The sulfur oxides and nitrogen oxides are related to two strong acids: sulfuric acid and nitric acid. When sulfur dioxide and nitrogen oxides are released into the air and are blown into areas where the weather is et, the acids can fall to the Earth in the rain, snow, fog or mist. In areas where the weather is dry, the acid chemicals may become incorporated into dusts or smokes. Acid rain can damage the environment, human health and property.

Acute Effect
An adverse effect on humans or animals, after a single significant exposure (e.g.) cyanide gas.

Administrative Order
A legal document signed by either a state or federal agency directing an individual, business or entity to take corrective action or refrain form an activity.

Administrator
The Administrator of the United States Environmental Protection Agency (USEPA).

Adsorption
A surface phenomenon (in contrast to absorption, which is an internal phenomenon) whereby molecules in a fluid phase are attracted to and held on a solid surface by a physical or weak chemical bond.

AEA
Atomic Energy Act (10 CFR, Parts 0 1--, 703 -1060)

Aerobic
The ability of living organisms to live and grow where free oxygen is present.

Aerosols
Liquid droplets or solid particles dispersed in air (0.01 to 100 microns).

Agency, The
United States Environmental Protection Agency

Agent Orange
A toxic herbicide and defoliant used in the Vietnam war, containing 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2-4 dichlorophenoxyacetic acid (2,4-D) with trace amounts of dioxin.

AHERA
Asbestos Hazard Emergency Response Act: (Title II of TSCA, 40 CFR 763): required schools to develop a "management plan" to address how to manage their ACM (Asbestos Containing Material).

AIChE
American Institute of Chemical Engineers

AIDS
Acquired Immune Deficiency Syndrome

AIHA
American Industrial Hygiene Association

Air Pollutant (Primary)
(CAA) Primary air pollutants are emitted directly into the atmosphere where they exert an adverse influence on human health or the environment. Examples of primary air pollutant are: CO2, CO, SOx, NOx, VOCs, and particulate matter.

Air Pollutant (Secondary)
Once a primary air pollutant has entered the atmosphere it may react with other primary pollutants or atmosphere compounds (such as water vapor) to form a secondary pollutant. Examples of secondary air pollutant are: acid rain and ozone.

AL
Action Level

ALARA
As Low As Reasonably Achievable

Alcohol
Organic compounds containing at least one hydrocarbon group and one hydroxyl group (R-OH).

Alkali
A hydroxide-containing compound that reacts with water to produce hydroxide ions ( OH- ) with a pH of greater than 7.0.

Alkane
A straight-chain hydrocarbon with the generic formula (CnH2n+2) containing a single carbon to carbon bond.

Alkene
A straight-chain unsaturated hydrocarbon containing a double bond with the generic formula: CnH2n.

Alkyne
A straight-chain unsaturated hydrocarbon containing a triple bond with the generic formula: CnH2n-2.

Alluvial
Relating to mud and/or sand deposited by flowing water.

AlphaEmitter
A radioactive material which emits alpha particles.

Alpha Particle (a)
A positively charged radioactive decay particle (double-charged helium ion, with a charge of +2 and a mass number of 4). Alpha particles are made up of two neutrons and two protons and are emitted by certain radioactive nuclei. Alpha particles can be stopped by thin layers of light materials, such as a sheet of paper, and pose no direct or external radiation threat; however, they can pose a serious health threat if ingested.

Alternative Fuels
Fuels that can replace ordinary gasoline, such as compressed natural gas, alcohols, liquefied petroleum gas (LPG) and electricity. The 1990 Clean Air Act encourages development and sale of alternative fuels.

Alum
A hydrated aluminum sulfate or potassium aluminum sulfate or ammonium aluminum sulfate which is used as a settling agent (a coagulant) in the treatment of water

Anhydrous
Free from water

Aliphatic Compound
A hydrocarbon consisting of carbon atoms arranged in either straight chains, branched chains and rings, but only containing single bonds.

Anaerobic
The ability of an organism to live, grow or take place where there is not air or free oxygen present.

Anion
An ion with a negative charge (e.g.) chloride: Cl-.

Annular Space
The space between the inner pipe (also called tubing) and the outer casing.

ANPRM
Advance Notice of Proposed Rulemaking

ANSI
American National Standards Institute

Antagonistic Effect
The simultaneous action of separate agents mutually opposing each other.

AOAC
Association of Official Analytical Chemists

AOC
Area of contamination (RCRA)

AP-42
EPA compilation of air pollution emission factors by source type.

API
American Petroleum Institute or American Paper Institute

API Separator
A primary physical wastewater treatment unit which removes free oil and settleable solids from water.

AQCR
Air Quality Maintenance Areas (40 CFR, Part 51)

ARAR
Applicable or Relevant and Appropriate Requirements; cleanup standards, control standards, criteria and limitations promulgated by Federal, State or local agencies.

Aromatic Compound
A ringed hydrocarbon (e.g. Ben zene)

Asbestos
Any material containing more than 1% asbestos.

ASME
American Society of Mechanical Engineers

ASSE
American Society of Safety Engineers

AST
Above Ground Storage Tank

ASTM
American Society for Testing & Materials

Asphyxiant
A substance which can cause death by suffocation (lack of oxygen).

ATM
Atmosphere (@ sea level 29.92 inches Hg or 14,7 PSI).

Atomic Number
The number of protons in the nucleus of an atom.

Atomic Weight
The relative mass of the atom on the basis of Carbon-12 (12C=12).

ATSDR
Agency for Toxic Substances & Disease Registry. Federal agency within the Public Health Service charged with carrying out the health related responsibilities of CERCLA and RCRA.

Attainment Area
A geographic area in which levels of a criteria air pollutant meet the health based primary standard (National Ambient Air Quality Standard, or NAAQS) for the pollutant. An area may have an acceptable level for one criteria air pollutant, but may have unacceptable levels for others. Thus, an area could be both attainment and non-attainment at the same time. Attainment areas are defined using federal pollutant limits set by EPA.

Autoignition Temperature
The minimum temperature at which a material will ignite without a spark or flame present.

AVGAS
Aviation Gas

AWMA
Air & Waste Management Association

AWQC
Ambient Waste Quality Criteria

AWWA
American Water Works Association

Azeotrope
A solution that does not change composition when distilled. For example, if a 95% (w/w) ethanol solution in water is boiled, the vapor produced also is 95% ethanol and it is not possible to obtain higher percentages of ethanol by distillation.