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Emission Standards Reference Guide

Light-Duty Vehicle and Light-Duty Truck -- Tier 1 and National Low Emission Vehicle Evaporative Emission Standards and Implementation Schedule

Vehicle Type Useful Life (years / miles) Evaporative Test Fuel Test Procedure
(2) 1-hour Hot Soaks (g/test) 3-Day Diurnal plus Hot Soak (g/test) 2-day Diurnal plus Hot Soak (g/test) Running Losses (g/mi) Spitback (grams fuel) ORVR (g/gal of fuel dispensed)
Federal Standard (Pre-enhanced) LDV 5 / 50,000 EPA Gasoline 2.0a - - - - -
Methanol (M10) 2.0b - - - - -
LDT 11 / 120,000 EPA Gasoline 2.0a, c - - - - -
Methanol (M10) 2.0b, c - - - - -
Enhanced Evaporative and ORVR LDV, LDT 1 & 2, LDT 3 & 4 ( < 30 gal fuel tank) 10 / 100,000
10 / 100,000
11 / 120,000
EPA Gasoline - 2.0a 2.5a 0.05a 1.0 0.2a
Methanol (M10) - 2.0b 2.5b 0.05b 1.0 0.2b
Ethanol (E10)d - 2.0b 2.5b 0.05b 1.0 0.2b
CNG - 2.0a - - - f
LPG - 2.0a - - - 0.15a
Diesel Fuel - - - - - 0.20a, g
LDT 3 & 4 ( < 30 gal fuel tank) 11 / 120,000 EPA Gasoline - 2.5a 3.0a 0.05a 1.0 0.2a
Methanol (M10) - 2.5b 3.0b 0.05b 1.0 0.2b
Ethanol (E10)d - 2.5b 3.0b 0.05b 1.0 0.2b
CNG - 2.0a - - - f
LPG - 2.0a - - - 0.15a
Diesel Fuel - - - - - 0.20a, g

 

Implementation Schedule

Vehicle Type Emission Standards Year
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Federal Pre-Enhanced LDV, LDT Cert & In-use 100% 80% max 60% max 10% max - - - - - Tier 2 Requirements Begin
Enhanced LDV, LDT Cert & In-usee - 20% min 40% min 90% min 100% 100% 100% 100% 100%
ORVR LDV, LDT Cert & In-usee - - - 40% min 80% min 100% 100% 100% 100%
LDT 1 & 2 Cert & In-usee - - - - - - 40% min 80% min 100%
LDT 3 & 4 Cert & In-usee - - - - - - - - - 40% min 80% min 100%

 

Notes:

a  Total hydrocarbon (THC).

b  Total hydrocarbon equivalent (THCE).

c  2.6 grams per test at high altitude prior to 1996 model year.

d  Compliance required for National Low Emission Vehicle (NLEV) and Clean Fuel Vehicle flexible fuel vehicles under defeat device regulations.

e  Small volume manufacturer exempt until last year of phase-in.

f  Must meet American National Standards Institute / American Gas Association Natural Gas Vehicle 1 (NGV) receptical requirements.

g  Waivers allowed.

Code of Federal Regulations (CFR) Citations:

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