Acronyms and Glossary
American Agricultural Law Association
The ability of a measurement to match the actual value of the quantity being measured.
Aerodynamic equivalent particle diameter
Allowable emission rate
Animal feeding operation. As defined by the U.S. Environmental Protection Agency (40 CFR 122.23), a “lot or facility” where animals “have been, are, or will be stabled or confined and fed or maintained for a total of 45 days or more in any 12 month period and crops, vegetation, forage growth, or post-harvest residues are not sustained in the normal growing season over any portion of the lot or facility.”
Caused by humans.
Administrative Procedure Act
Air Pollution Regulatory Process
Agricultural Research Service (USDA)
American Society of Agricultural Engineers
Aerosol mass spectrometer
American Society for Testing and Materials
a property that depends on inversion strength—how rapidly air temperature rises with altitude (in units of degrees Celsius per 100 m). Strong inversions near the ground tend to stabilize the atmosphere, trap emissions, and result in higher pollutant concentrations. For a discussion of meteorological effects on carbon monoxide concentrations, see NRC (2002b).
AU: Animal unit:
A unit of measure used to compare different animal types.
• EPA (66 Fed. Reg. 2960-3138): 1 cattle excluding mature dairy and veal cattle; 0.7 mature dairy cattle; 2.5 swine weighing more than 55 pounds; 10 swine weighing 55 pounds or less; 55 turkeys; 100 chickens; and 1 veal calf.
• USDA: 1000 pounds of live animal weight.
Best achievable control technology
A unit of pressure equal to one atmosphere (14.7 pounds per square inch).
Best available technology (economically achievable)
Particulate matter in the atmosphere containing materials of biological origin that may cause disease, such as toxins, allergens, viruses, bacteria, and fungi.
Best management practice
Biochemical oxygen demand
Best practicable control technology (currently available)
C2, C10, C16:
Hydrocarbons with 2, 10, and 16 carbon atoms, respectively.
Clean Air Act
Concentrated animal feeding operation (see Appendix E).
Commodity Credit Corporation, a government-owned and operated corporation, was created in 1933 to stabilize, support, and protect farm income and prices. It now operates as a federal corporation within USDA; the Secretary of Agriculture chairs its Board of Directors. CCC programs are carried out through the personnel and facilities of other USDA organizations, including the Farm Service Agency and the Natural Resources Conservation Service. CCC funds are used for a number of conservation programs, include EQIP (67 Fed. Reg. 48431), the Conservation Reserve Program, the Wetlands Reserve Program, and the Farmland Protection Program.
Cloud condensation nuclei
Comprehensive Environmental Response, Compensation, and Liability Act
Cubic feet per minute
Code of Federal Regulations
Colony forming units (bacteria formed on nutrient media)
Comprehensive Nutrient Management Plan
Chemical oxygen demand
Conservation Reserve Program
Conservation Security Program
Cooperative State Research, Education, and Extension Service (USDA)
Clean Water Act
Coastal Zone Act Reauthorization Amendments
Coastal Zone Management Act
Reduction of nitrates or nitrites to nitrogen-containing gases.
Dairy Herd Improvement Association
Dry matter intake
Differential optical absorption spectroscopy
Dry standard cubic meter
An array of gas sensors that are combined with pattern recognition software to mimic human olfactory response (Lacey, 1998).
Effluent limitation guideline
The rate of mass emission per unit of area (e.g., tonnes per hour per hectare), typically from an area such as a waste lagoon or field.
A list showing the sources and amounts (e.g., tonnes) of a pollutant emitted from a defined area for a period of time, usually one year.
The rate of mass emission (e.g., tonnes per hour).
U.S. Environmental Protection Agency
Emergency Planning and Community Right-to-Know Act
Environmental Quality Incentives Program
An animal feeding operation where beef cattle are finished to slaughter weight; it consists of fenced earthen or concrete paddocks with cattle having little of no access to pasture.
Flame ionization detector
Flame photometric detector
Federal reference method
Farm Service Agency (USDA)
Fourier Transform Infrared Spectroscopy
Grams per cubic centimeter
Gas chromatography with electron capture detection
Gas chromatography with flame ionization detection
Gas chromatography coupled with mass spectrometry
Ground-level area source
Hectare; an area 100 meters square, about 2.5 acres
Hazardous air pollutant
Hertz (cycles per second)
Intergovernmental Panel on Climate Change
Industrial Source Complex Short Term
Kilogram, or 1000 grams (about 2.2 pounds)
Kilometer, or 1000 meters
Lowest achievable emission rate
The dose lethal to 50 percent of the laboratory animals tested.
Light detection and ranging. A device similar to radar except that it emits pulsed laser light rather than microwaves.
Low-level point source
Lowest observed adverse effect level
Live unit, 500 kg of body weight
Maximum achievable control technology
A mixture of animal feces and urine, which may also include litter or bedding materials.
Methane conversion factor
megagram. An SI unit of mass equal to 1 million grams or 1000 kg. This means that the megagram is identical to the tonne (metric ton). Large masses are almost always stated in tonnes in commercial applications, but megagrams are often used in scientific contexts. One megagram equals about 2204.623 pounds.
Micrograms per cubic meter
Micrometer or micron (10−6 meter)
Mass median diameter
Millions of metric tonnes carbon equivalent (used to express the greenhouse effect of methane and other gases relative to carbon dioxide).
Milk urea nitrogen
Midwest Plan Service (an organization of extension and research agricultural engineers).
National Ambient Air Quality Standards
National Bureau of Standards (now NIST)
National Emission Standards for Hazardous Air Pollutants
National Institute of Standards and Technology
Oxidation of ammonia or an ammonium ion compound to nitric acid, nitrous acid, or any nitrate or nitrite, especially by the action of nitrobacteria.
No observed adverse effect level
Notice of data availability
Notice of violation
NO and NO2 (rapidly interconverted in the atmosphere)
All oxidized nitrogen species in the atmosphere
National Pollutant Discharge Elimination System
Reactive nitrogen (all nitrogen other than N2). The term reactive nitrogen (Nr) is used in this report to denote all biologically active, photochemically reactive, and radiatively active nitrogen compounds in the atmosphere and biosphere of the earth and to distinguish all reactive forms of nitrogen from nonreactive gaseous dinitrogen (N2). Thus, Nr includes (1) inorganic reduced forms of nitrogen (e.g., NH3, NH4+), (2) inorganic oxidized forms of nitrogen (e.g., NOx, HNO3, N2O, NO3−), and (3) a wide variety of organic nitrogen compounds including urea, amino acids, amines, proteins, nucleic acids, and so forth.
National Research Council
Natural Resources Conservation Service (USDA)
New Source Performance Standards
New source review
NIST Traceable Reference Material
Nitrogen utilization efficiency (the ratio of nitrogen in animal product to nitrogen in feed consumed).
Nutrient excretion factor:
An estimate of the amount of a nutrient element (e.g., N) excreted, usually reported as kilograms per day (or year) per animal (or animal unit or kilograms of body weight).
Odor detection threshold. The minimum concentration of odorant(s) detectable by 50 percent of the population (represented by an odor panel).
Odor unit. The amount of odorant(s) in 1 m3 of air detectable by 50 percent of the population
European odor unit is the amount of odorant(s) that, when evaporated into 1 cubic meter of neutral gas at standard conditions, elicits a physiological response from a panel (detection threshold) equivalent to that elicited by 1 European Reference Odor Mass (erom), evaporated in 1 m3 of neutral gas at standard conditions. One erom is equivalent to 123 mg n-butanol (CAS 71-36-3).
Planetary boundary layer
Polymerase chain reaction
Photolytic fragmentation laser-induced fluorescence
Particulate matter having an aerodynamic diameter of 2.5 μm or less.
Particulate matter having an aerodynamic diameter of 10 μm or less.
Permit nutrient plan
“[A]ny discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel,…concentrated animal feeding operation,…from which pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture” (33 USC § 1362(14)).
Parts per billion (by volume)
Pounds per day
Parts per million (by volume)
The degree of agreement between two or more results on the same property of identical test material expressed as the repeatability or reproducibility of an instrument reading the results.
Particle size distribution
Prevention of significant deterioration
Pounds per square inch
Relaxed eddy accumulation
Rolling herd average
Reactive organic gase
State air pollution regulatory agency
Sulfur chemiluminescence detector
Sulfur hexafluoride (used as an atmospheric tracer)
State implementation plan
Single point air monitor
Solid-phase microextraction. A method used to concentrate the components in odor samples prior to analysis.
Standard reference material
Standard temperature and pressure, dry
Relating to weather conditions that exist simultaneously over a large area.
Total ammoniacal nitrogen
Tunable diode laser spectroscopy
Teragram. 1 × 1012 g, or 1 million metric tonnes
Total Kjeldahl nitrogen
Total maximum daily load
Texas Natural Resource Conservation Commission
Tons (short) per year
Total reduced sulfur (includes H2S and mercaptans)
Total suspended particulates
The estimated amount or percentage by which an observed or calculated value may differ from the true value.
United States Code
U.S. Department of Agriculture
U.S. Department of Commerce
Volatile fatty acid
Volatile organic compound
Volatile solids. The weight lost upon ignition at 550 °C—an approximation of moisture and organic matter present (using Method 2540 E of the American Public Health Association).