| AEP | American Electric Power |
| CAA | Clean Air Act |
| CARB | California Air Resources Board |
| CCME | Canadian Council of Ministers of the Environment |
| CEC | Commission for Environmental Cooperation |
| CEPA | Canadian Environmental Protection Act |
| CWG | Coal Boiler Workgroup |
| CWS | Canada-wide Standards |
| DE | diesel exhaust |
| DPM | diesel particulate matter |
| E-GRID | Emissions & Generation Resource Integrated Database |
| EBR | Environmental Bill of Rights |
| EGU | electrical generating units |
| EIA | Electrical Industry Association |
| EPS(s) | Emissions Performance Standard(s) |
| ERCs | Emission Reduction Credits |
| EU | European Union |
| FERC | Federal Energy Regulatory Commission |
| FRM | Federal Reference Method |
| g/bhp-hr | grams per brake horsepower-hour |
| HCl | hydrochloric acid |
| HHD | heavy heavy-duty |
| HLDT(s) | heavy light-duty truck(s) |
| IAQAB | International Air Quality Advisory Board |
| ICI | industrial/commercial/institutional |
| IJC | International Joint Commission |
| IPCC | Intergovernmental Panel on Climate Change |
| LHD | light heavy-duty |
| LLDT(s) | light light-duty truck(s) |
| MD | medium duty |
| MDPV(s) | medium-duty passenger vehicle(s) |
| MTBE | Methyl Teritary Butyl Ether |
| NO 2 | nitrogen dioxide |
| NO x | nitrogen oxides |
| NPRM | notice of proposed rulemaking |
| NSPS | New Source Performance Standard |
| O 3 | ozone |
| OPG | Ontario Power Generation |
| OTAG | Ozone Transport Assessment Group |
| OTC | Ozone Transport Commission |
| PAH(s) | polyaromatic hydrocarbon(s) |
| PCF | Prototype Carbon Fund |
| PM | particulate matter |
| PM 10 | Coarse particulate matter |
| PM 2.5 | Fine particulate matter |
| RfC | Inhalation Reference Concentration |
| RFG | reformulated gasoline |
| SIP(s) | State Implementation Plan(s) |
| SO 2 | Sulfur dioxide |
| SUV(s) | sport utility vehicle(s) |
| TEOM | Tapered Element Oscillating Balance Monitor |
| TPY | tons per year |
| TRI | Toxics Release Inventory |
| TSP | Total Suspended Particulate |
| TVA | Tennessee Valley Authority |
| ULSD | ultra low sulfur diesel |
| UNFCCC | United Nations Framework Convention on Climate Change |
| USEPA | United States Environmental Protection Agency |
| VOC(s) | volatile organic compounds(s) |