United States Air and Radiation EPA420-F-98-017 Environmental Protection April 1998 Agency Office of Mobile Sources &EPA Regulatory Announcement Final Rule Amendment to On-Board Diagnostic Checks Requirement for I/M Programs The U.S. Environmental Protection Agency (EPA) is extending, by a period of three years, the deadline by which states must implement On- Board Diagnostic (OBD) checks as a regular part of their Inspection and Maintenance (I/M) programs. Prior to this new deadline of January 1, 2001, states may opt to include OBD checks and fail vehicles based on OBD failure alone. States may not earn emission reduction credit, however, unless exhaust and evaporative tests are performed as well. Should EPA and states complete testing and review of OBD systems sooner than expected, the Agency may be able to make credits available to states who choose to implement OBD I/M checks prior to the new deadline. Background On August 6, 1996, EPA published a final rulemaking relating to the implementation of OBD checks as a routine part of I/M programs. In the rule, EPA interpreted the Clean Air Act requirement to include both emission testing and OBD checks and thus required both tests as part of the regular I/M test procedures. Ozone Transport Region (OTR) areas with OTR low enhanced programs were to implement OBD checks by January 1, 1999, and all other areas were to implement OBD checks by January 1, 1998. Until January 1, 2000, OBD checks, exhaust tests and evaporative system tests, where applicable, were to be required on each subject vehicle of model year 1996 and newer. After January 1, 2000, > Printed on Recycled Paper ------- failure of the OBD test would require mandatory repair. On December 22, 1997, EPA published a Notice of Proposed Rulemaking (NPRM) (62 FR 66841) which proposed delaying the implementation of mandatory OBD checks until January 1, 2001. Overview of Final Rule This rule delays the required implementation date for OBD by setting the new implementation deadline as January 1, 2001, for all areas with basic and enhanced I/M programs. This amounts to a two year delay for OTR low enhanced areas and a three year delay for all others. During this time extension, EPA will work with states and other stakeholders to generate, collect and analyze the data necessary to determine the effectiveness of OBD systems in an I/M setting. EPA is currently conducting such a study which began October 1, 1997. Two years are needed to ensure ample time for fleet penetration of OBD- equipped vehicles, so that enough vehicles can be recruited for the study. A third year will be needed to allow sufficient time to analyze the data generated by the study. In addition, EPA has made certain clarifying amendments to allow for updates to the Code of Federal Regulations which are cross-referenced in the OBD rule. Section 86.094-17, which includes the technical specifica- tions for OBD systems, is periodically updated to include new require- ments. This rule amends the sections of the OBD rule where that subsec- tion is referenced with new language which obviates the need for future amendments in this regard. This rule does not affect the requirement that states revise their I/M State Implementation Plans by August 6, 1998, to include the OBD checks. Also unchanged are the sections which allow states the option to imple- ment OBD inspections before December 31, 1999, and to allow failure of OBD to result in failure of the I/M test, thereby requiring repair. However, states which choose to conduct OBD checks cannot earn emission reduction credits for doing so unless they also perform the exhaust and evaporative tests, where applicable, or unless EPA completes its analysis and determines appropriate credit sooner than expected. ------- Effect of Final Rule This rule will allow the states even greater flexibility in designing and implementing I/M programs which meet their local needs and help them to move towards attainment. In addition, it will reduce the cost burden the states would face if they were required to run OBD checks concur- rently with the exhaust and evaporative tests as required by the previous rule, so this amendment will produce a net savings. The I/M testing requirements will now be less burdensome in terms of test time, equip- ment and cost. Furthermore, it is not certain that the requirement would have generated additional emission reductions to justify the added cost. OBD equipment suppliers and I/M contractors may need to adjust to shifting requirements resulting from this rule. Automobile manufacturers may see a delay in the generation of some data on OBD in-use perfor- mance. The general public will not be affected by the delay, as it only postpones a requirement to which most have not yet been subjected. The delay will have no appreciable effect upon the environment. The vehicles which would otherwise be subject to the OBD check will still receive exhaust and evaporative (where applicable) testing, if the state is earning emission reduction credits for those vehicles. Emission reduc- tions will still be achieved for those vehicles despite the delay in OBD checks. For More Information Additional documents on I/M programs and OBD are available electroni- cally from the EPA Internet server at: http ://www. epa.gov/OMSWWW/im.htm Document information is also available by writing to: U.S. Environmental Protection Agency Office of Mobile Sources 2565 Plymouth Road Ann Arbor, Michigan 48105 ------- |