Enclosure (3) to COMDTINST 4454.1
II.
I/M Program
A.
Technical Requirements
The I/M technical requirements are outlined in the SIP for each state or local nonattainment
area listed in enclosure (1). Because of the diversity of nonattainment areas and state
requirements, each SIP will be different; only the general requirements as listed in 40 CFR
Part 51 Subpart S are discussed here. States can adopt more stringent test standards for older
vehicles, but ultimately EPA must approve the SIP. The high enhanced, alternate low
enhanced, and basic I/M test requirements as well as an explanation of key terms are
described below.
1.
High Enhanced Test
Start Date:
January 1, 1995 (The date the State must begin testing)
Testing
Annually (biannually allowed if State can demonstrate attainment)
Model Year
Coverage:
Covers 1968 and later vehicles
Vehicles
Covered:
Light duty cars and light duty trucks, rated up to 8,500 pounds Gross
Vehicle Weight Rating (GVWR)
Waiver
costs:
Minimum 0 spent for repairs, adjusted for inflation.
Test Type
Idle or two speed test, plus visual
2.
Alternate Low Enhanced Test
This revision to the standards is for nonattainment areas that are required to implement
high enhanced testing (#1 above) but which can obtain adequate emission reductions
from other sources without the stringency of enhanced testing (see reductions in waiver
costs and test type below).
Start Date:
18 Oct 1995
Testing
Annually
5
Previous Page
