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Emission Standards Reference Guide

Light-Duty Truck -- Tier 0, Tier 1, and Clean Fuel Vehicle Exhaust Emission Standards

Vehicle Type Emission Category Vehicle Useful Life
5 Years / 50,000 Miles 10 Years / 100,000 Miles
NMHCa (g/mi) NMOG (g/mi) COb, c NOxd (g/mi) PM (g/mi) HCHO (g/mi) THCc, e, f (g/mi) NMHCa (g/mi) NMOG (g/mi) COg (g/mi) NOx (g/mi) PM (g/mi) HCHO (g/mi)
Federalh, i, j LDT3 Tier 0 - - - - - - 0.8 0.67k - 10 1.7 0.26l -
Tier 1 0.32 - 4.4 0.7 - - 0.8 0.46 - 6.4 0.98 0.1 -
LDT4 Tier 0 - - - - - - 0.8 0.67k - 10 1.7 0.13l -
Tier 1 0.39 - 5 1.1 - - 0.8 0.56 - 7.3 1.53 0.12 -
Federal Clean Fuel Vehicle (CFV) Programh, i LDT3
0-3750
ALVW
LEV - 0.125n 3.4 0.4 - 0.015 - - 0.180n 5 0.6 0.08o 0.022
ILEVm - 0.125 3.4 0.2 - 0.015 - - 0.180 5 0.3 0.08o 0.022
ULEV - 0.075n 1.7 0.2 - 0.008 - - 0.107n 2.5 0.3 0.04o 0.012
LDT3
3751-5750
ALVW
LEV - 0.160n 4.4 0.7 - 0.018 - - 0.230n 6.4 1.0 0.10o 0.027
ILEVm - 0.160 4.4 0.4 - 0.018 - - 0.230 6.4 0.5 0.10o 0.027
ULEV - 0.100n 2.2 0.4 - 0.009 - - 0.143n 3.2 0.5 0.10o 0.013
LDT4
5751-8500
ALVW
LEV - 0.195n 5 1.1 - 0.022 - - 0.280n 7.3 1.5 0.12o 0.032
ILEVm - 0.195 5 0.6 - 0.022 - - 0.280 7.3 0.8 0.12o 0.032
ULEV - 0.117n 2.5 0.6 - 0.011 - - 0.167n 3.7 0.8 0.06o 0.016
Notes:  
Tests Covered: Federal Test Procedure (FTP), cold carbon monoxide (CO), highway, and idle
Effective Model Year: 1981 - 1993, Tier 0
1994 - 1999, Tier 1
1999 - Present, CFV

a  Total hydrocarbon equivalent (THCE) for Tier 0 methanol vehicles, non-methane hydrocarbon equivalent (NMHCE) for other alcohol vehicles.

b  Cold CO emissions for gasoline fueled vehicles shall not exceed 10.0 grams per mile (g/mi) (light-duty vehicle, light-duty truck 1 [LDT1], LDT2) or 12.5 g/mi (LDT3 & LDT4) at 50,000 miles.

c  Cerification short test (CST) emissions from gasoline vehicles shall not exceed 100 parts per million HC or 0.50 percent exhaust gas CO at idle and 2500 revolutions per minute at 4,000 miles; compliance statement allowed in lieu of actual test data.

d  Does not apply to diesel-fueled vehicles.

e  THCE for methanol vehicles.

f  Does not apply to compressed natural gas (CNG) vehicles.

g  Idle CO emissions from gasoline, methanol, CNG and liquefied petroleum gas trucks shall not exceeed 0.50 percent exhaust gas at 120,000 miles or 11 years; compliance statement allowed in lieu of actual test data.

h  Federal On-board diagnostics system required beginning with 1994 model year vehicles.

i  Tier 1, National Low Emissions Vehicle (NLEV) & CFV vehicles must meet Tier 1 emissions standards at high altitude; Tier 0 vehicles must meet special high altitude standards; compliance statement allowed in lieu of actual test data.

j  Tier 0 and Tier 1 emission standards do not apply to ethanol vehicles.

k  CNG vehicles only.

l  Diesel-fueled vehicles only.

m  Special evaporative requirements apply (5.0 grams maximum with the evaporative system disconnected).

n  Special non-methane organic gas (NMOG) standards apply to dual and flexible fuel vehicles.

o  Diesel-fueled vehicles only.

Code of Federal Regulations (CFR) Citations:

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