40 CFR § 51.352 - Basic I/M performance standard.
(a) Basic I/M programs shall be designed and implemented to meet or exceed a minimum performance standard, which is expressed as emission levels achieved from highway mobile sources as a result of the program. The performance standard shall be established using the following model I/M program inputs and local characteristics, such as vehicle mix and local fuel controls. Similarly, the emission reduction benefits of the State's program design shall be estimated using the most current version of the EPA mobile source emission model, and shall meet the minimum performance standard both in operation and for SIP approval.
(1) Network type. Centralized testing.
(2) Start date. For areas with existing I/M programs, 1983. For areas newly subject, 1994.
(3) Test frequency. Annual testing.
(4) Model year coverage. Testing of 1968 and later model year vehicles.
(5) Vehicle type coverage. Light duty vehicles.
(6) Exhaust emission test type. Idle test.
(7) Emission standards. No weaker than specified in 40 CFR part 85, subpart W.
(8) Emission control device inspections. None.
(9) Stringency. A 20% emission test failure rate among pre-1981 model year vehicles.
(10) Waiver rate. A 0% waiver rate.
(11) Compliance rate. A 100% compliance rate.
(12) Evaluation date. Basic I/M programs shall be shown to obtain the same or lower emission levels as the model inputs by 1997 for ozone nonattainment areas and 1996 for CO nonattainment areas; and, for serious or worse ozone nonattainment areas, on each applicable milestone and attainment deadline, thereafter.
(b) Oxides of nitrogen. Basic I/M testing in ozone nonattainment areas shall be designed such that no increase in NOX emissions occurs as a result of the program. If the Administrator finds, under section 182(b)(1)(A)(i) of the Act pertaining to reasonable further progress demonstrations or section 182(f)(1) of the Act pertaining to provisions for major stationary sources, that NOX emission reductions are not beneficial in a given ozone nonattainment area, then the basic I/M NOX requirement may be omitted. States shall implement any required NOX controls within 12 months of implementation of the program deadlines required in § 51.373 of this subpart, except that newly implemented I/M programs shall include NOX controls from the start.
(c) On-board diagnostics (OBD). For those areas required to implement a basic I/M program prior to the effective date of designation and classification under the 8-hour ozone standard, the performance standard shall include inspection of all model year 1996 and later light-duty vehicles equipped with certified on-board diagnostic systems, and repair of malfunctions or system deterioration identified by or affecting OBD systems as specified in § 51.357, and assuming a start date of 2002 for such testing. For areas required to implement basic I/M as a result of designation and classification under the 8-hour ozone standard, the performance standard defined in paragraph (e) of this section shall include inspection of all model year 2001 and later light-duty vehicles equipped with certified on-board diagnostic systems, and repair of malfunctions or system deterioration identified by or affecting OBD systems as specified in § 51.357, and assuming a start date of 4 years after the effective date of designation and classification under the 8-hour ozone standard.
(d) Modeling requirements. Equivalency of emission levels which will be achieved by the I/M program design in the SIP to those of the model program described in this section shall be demonstrated using the most current version of EPA's mobile source emission model and EPA guidance on the estimation of input parameters. Areas required to implement basic I/M programs shall meet the performance standard for the pollutants which cause them to be subject to basic requirements. Areas subject as a result of ozone nonattainment shall meet the standard for VOCs and shall demonstrate no NOX increase, as required in paragraph (b) of this section.
(e) Basic performance standard for areas designated non-attainment for the 8-hour ozone standard. Areas required to implement a basic I/M program as a result of being designated and classified under the 8-hour ozone standard, must meet or exceed the emission reductions achieved by the model program defined for the applicable ozone precursor(s):
(1) Network type. Centralized testing.
(2) Start date. 4 years after the effective date of designation and classification under the 8-hour ozone standard.
(3) Test frequency. Annual testing.
(4) Model year coverage. Testing of 1968 and newer vehicles.
(5) Vehicle type coverage. Light duty vehicles.
(6) Emission test type. Idle testing (as described in appendix B of this subpart) for 1968–2000 vehicles; onboard diagnostic checks on 2001 and newer vehicles.
(7) Emission standards. Those specified in 40 CFR part 85, subpart W.
(8) Emission control device inspections. None.
(9) Evaporative system function checks. None, with the exception of those performed by the OBD system on vehicles so-equipped and only for model year 2001 and newer vehicles.
(10) Stringency. A 20% emission test failure rate among pre-1981 model year vehicles.
(11) Waiver rate. A 0% waiver rate, as a percentage of failed vehicles.
(12) Compliance rate. A 100% compliance rate.
(13) Evaluation date. Basic I/M program areas subject to the provisions of this paragraph (e) shall be shown to obtain the same or lower emission levels as the model program described in this paragraph by an evaluation date set 6 years after the effective date of designation and classification under the 8-hour ozone standard (rounded to the nearest July) for the applicable ozone precursor(s).