CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER C—AIR PROGRAMS (Parts 50–99) > PART 51—REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS > SUBPART S—Inspection/Maintenance Program Requirements (§51.350 to §51.373) > 51.358—Test equipment.

51.358—Test equipment.

Computerized emission test systems are required for performing an official emissions test on subject vehicles.
(a) Performance features of computerized emission test systems. The emission test equipment shall be certified by the program, and newly acquired emission test systems shall be subjected to acceptance test procedures to ensure compliance with program specifications.
(1) Emission test equipment shall be capable of testing all subject vehicles and shall be updated from time to time to accommodate new technology vehicles as well as changes to the program. In the case of OBD-based testing, the equipment used to access the onboard computer shall be capable of testing all MY 1996 and newer, OBD-equipped light-duty vehicles and light-duty trucks.
(2) At a minimum, emission test equipment:
(i) Shall make automatic pass/fail decisions;
(ii) Shall be secured from tampering and/or abuse;
(iii) Shall be based upon written specifications; and
(iv) Shall be capable of simultaneously sampling dual exhaust vehicles in the case of tailpipe-based emission test equipment.
(3) The vehicle owner or driver shall be provided with a record of test results, including all of the items listed in 40 CFR part 85, subpart W as being required on the test record (as applicable). The test report shall include:
(i) A vehicle description, including license plate number, vehicle identification number, and odometer reading;
(ii) The date and time of test;
(iii) The name or identification number of the individual(s) performing the tests and the location of the test station and lane;
(iv) The type(s) of test(s) performed;
(v) The applicable test standards;
(vi) The test results, by test, and, where applicable, by pollutant;
(vii) A statement indicating the availability of warranty coverage as required in section 207 of the Clean Air Act;
(viii) Certification that tests were performed in accordance with the regulations and, in the case of decentralized programs, the signature of the individual who performed the test; and
(ix) For vehicles that fail the emission test, information on the possible cause(s) of the failure.
(b) Functional characteristics of computerized emission test systems. The test system is composed of motor vehicle test equipment controlled by a computerized processor and shall make automatic pass/fail decisions.
(1) [Reserved]
(2) Test systems in enhanced I/M programs shall include a real-time data link to a host computer that prevents unauthorized multiple initial tests on the same vehicle in a test cycle and to insure test record accuracy. For areas which have demonstrated the ability to meet their other, non-I/M Clean Air Act requirements without relying on emission reductions from the I/M program (and which have also elected to employ stand-alone test equipment as part of the I/M program), such areas may adopt alternative methods for preventing multiple initial tests, subject to approval by the Administrator.
(3) [Reserved]
(4) On-board diagnostic test equipment requirements. The test equipment used to perform on-board diagnostic inspections shall function as specified in 40 CFR 85.2231.
(c) SIP requirements. The SIP shall include written technical specifications for all test equipment used in the program and shall address each of the above requirements (as applicable). The specifications shall describe the testing process, the necessary test equipment, the required features, and written acceptance testing criteria and procedures.

Code of Federal Regulations

[57 FR 52987, Nov. 5, 1992, as amended at 61 FR 40945, Aug. 6, 1996; 65 FR 45533, July 24, 2000; 66 FR 18178, Apr. 5, 2001]