Table 4-6b,,,,, Federal Emission Control Requirements for Heavy Trucks:,,,,, Model Year,,,,, (Grams of emissions per brake horsepower-hour),,,,, ,,,,, ,,Carbon,,, ,Total,monoxide,Nitrogen,,Smoke ,hydrocarbons,(CO),oxides,Particulates,(percentage) ,,,,, Mexico,,,,, " Compression ignition, model years 1994-1997 ",1.3,15.5,5.0,0.7 or 0.10,20/15/50 " (weight more than 3,857 kg)",,,,, " Spark ignition, model years 1995-1997",,,,, " Weight between 3,858 and 6,350 kg ",1.1,14.4,5.0,NA,NA " Weight greater than 6,350 kg ",1.9,37.1,5.0,NA,NA ,,,,, "United States and Canada, model years",,,,, 1994 and later,,,,, " Compression ignition, model years 1994-1997 ",1.3,15.5,5.0,0.1,20/15/50 " (weight more than 3,856 kg; i.e., more than",,,,, " 8,500 pounds)",,,,, " Spark ignition, model years 1991-1997",,,,, " Weight between 3,856 and 6,350 kg ",1.1,14.4,5.0,NA,NA " Weight greater than 6,350 kg ",1.9,37.1,5.0,NA,NA KEY: NA = Not applicable.,,,,, NOTES,,,,, All Countries,,,,, "Compression ignition, smoke: Percentages apply to smoke opacity at acceleration/lug/peak modes.",,,,, Canada,,,,, "From September 1, 1997, Canadian standards are harmonized with U.S. standards by regulation, for all classes of on-road vehicles.",,,,, "Heavy trucks: For heavy trucks (heavy-duty vehicles), Canadian vehicles were provided to U.S. standards by a Memorandum of",,,,, Understanding with the industry.,,,,, Mexico, "Compression ignition, particulates: The limit is 0.10 for vehicles under 14,969 kg and 0.7 for vehicles over 14,969 kg.", United States, Compression ignition: Standards apply to both diesel and methanol-fueled engines., "Spark ignition: Standards apply to gasoline, methanol and liquified petroleum gas-fueled engines (LPG).", "Spark ignition, weights: The first category of spark ignition heavy trucks in this table weighs more than 8,500 pounds and weighs", "14,000 pounds or less. The second category weighs more than 14,000 pounds.", SOURCES, Canada, "Transport Canada. Road Safety and Motor Vehicle Regulations Directorate. (Ottawa, Ont.: 1998).", Mexico, "Instituto Nacional de Ecología. Diario Oficial de la Federación. Norma Oficial Mexicana NOM-044-ECOL-1993. (Mexico City, D.F.:", 1993)., "Secretaría de Medio Ambiente, Recursos Naturales y Pesca. Diario Oficial de la Federación. Norma Oficial Mexicana NOM-076-ECOL-", "1995. (Mexico City, D.F.: 1995).", United States, U.S. Environmental Protection Agency. Office of Air and Radiation. Emission Standards Reference Guide for Heavy-Duty and Nonroad "Engines (EPA420-F-97-014). (Washington, DC: 1997)." "U.S. Environmental Protection Agency. Office of Air and Radiation. Mobile Source Emissions Standards Summary. (Washington, DC:" 1992).