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The BTS Pocket Guide to Transportation is a popular, quick reference guide that provides transportation statistics at your fingertips. It provides key information and highlights major trends on the U.S. transportation system.
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KEY: O3 = ozone; Pb = lead; PM-10 = particulate matter smaller than 10 micrometers; PM-2.5 = particulate matter smaller than 2.5 micrometers; SO2 = sulfur dioxide.
a States are listed alphabetically. Some states on a row may be nonattainment for some pollutants and not for others in the general area. A multi-state area with states that have not all been redesignated to maintenance is counted as a nonattainment area until all of the states in the area are redesignated, with the whole area...
KEY: CO = carbon monoxide; g/kW-hr = gram per kilowatt-hour; HC = hydrocarbons; THC = total hydrocarbon; kW = kilowatt; NOx = nitrogen oxides; PM = particulate matter; rpm = revolutions per minute.
a Tier 2 emissions standards established by Congress apply to commercial compression-ignition (diesel) engines with a power rating of at least 37 kW. Both propulsion and auxiliary engines are covered under these standards, but land-based engines used in portable auxiliary equipment must meet standards for land-based engines. Smaller compression-ignition engines are...
KEY: CO = carbon monoxide; g = gram; g/kN = grams of pollutant per kilonewtons of thrust; HC = hydrocarbon, kN = kilonewtons; kW = kilowatt; NOx = nitrogen oxides; rO = rated output, which is the maximum power or thrust available for takeoff; rPR = rated pressure ratio.
a Federal standards apply to all planes operating in the United States, regardless of where they were manufactured. This table primarily displays exhaust emissions standards for newly manufactured aircraft engines. Only two standards (smoke standards) have been set for in-use aircraft...
KEY: cc = cubic centimeters; g = gram; HC = hydrocarbon; CO = Carbon Monoxide; kg = kilogram; km = kilometer; lb = pound; mi = miles; mph = miles per hour; NOx = Nitrogen Oxides.
a A motorcycle is any motor vehicle with a headlight, taillight, and stoplight, and having two or three wheels and a curb mass less than or equal to 793 kg (1,749 lb). (The limit was 680 kg, or 1,499 lb prior to the 1998 model year.) A motorcycle is excluded from the standards if it has a displacement of less than 50 cc (3.1 cubic inches) or if with a 80 kg (176 lb) driver it cannot start...
KEY: CO = carbon monoxide; HC = hydrocarbon; NOx = nitrogen oxides; NMHC = nonmethane hydrocarbons.
a Smoke opacity is expressed in percentage for acceleration, lugging, and peak modes (acceleration/lugging/peak). Lugging is when a vehicle is carrying a load.
b Gross vehicle weight rating (GVWR) is the maximum design loaded weight.
c Several testing procedures have been used during the course of exhaust emissions control. A steady-state 9-mode test procedure (13-mode for diesel) was used for 1970-83 standards. For 1984, either...
KEY: CO = carbon monoxide; HC = hydrocarbon; NOx = nitrogen oxides; NMHC = nonmethane hydrocarbons; NMOG = nonmethane organic gas; HCHO = formaldeyhyde.
a Smoke opacity is expressed in percentage for acceleration, lugging, and peak modes (acceleration/lugging/peak). Lugging is when a vehicle is carrying a load.
b Gross vehicle weight rating (GVWR) is the maximum design loaded weight.
c Several testing procedures have been used during the course of exhaust emissions control. A steady-state 9-mode test procedure (13-mode...
KEY: CO = carbon monoxide; g/bhp-hr = grams per brake horsepower/hour; GVWR = gross vehicle weight rating; HC = hydrocarbons; NMHC=nonmethane hydrocarbon; NMOG = nonmethane organic gases; NOx = nitrogen oxides.
a The MDPV category was created for the Interim Tier 2 and Tier 2 vehicle emissions standards. This category was specifically designed to help bring passenger vehicles (such as large sport utility vehicles and passenger vans) over 8,500 pounds GVWR into the Tier 2 program. MDPVs are defined as any complete heavy-duty vehicle less than 10,000 pounds GVWR...