Vehicle Emissions Inspection and Maintenance (I/M): Policy, Guidance and Test Procedures
- Policy guidance on inspection and maintenance (I/M) program implementation
- Inspection and Maintenance (I/M) Procedures
- IM240 Technical Guidance
- Acceleration Simulation Modes (ASM)
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Policy guidance on inspection and maintenance (I/M) program implementation.
- December 2016 policy guidance entitled Vehicle Emission Inspection and Maintenance (I/M) Provision in the Fixing America’s Surface Transportation (FAST) Act provides clarification regarding the obligations of states versus EPA with regard to the I/M provision of the FAST Act exempting certain replica vehicles from I/M.
- February 2014 modeling guidance document entitled Performance Standard Modeling for New and Existing Vehicle Inspection and Maintenance (I/M) Programs Using the MOVES Mobile Source Emissions Model (PDF) (25 pp, 246K, EPA-420-B-14-006, January 2014) provides clarification on how to quantify I/M emission reductions for planning purposes using the MOVES generation of mobile source emission factor models, including a discussion of I/M modeling changes since the previous mobile source emission factor model, MOBILE. This guidance corrects technical issues identified in an earlier version released November 2013 (23 pp, 242K, EPA-420-B-13-059, November, 2013). The current version replaces that earlier document.
- May 12, 2004 policy memo signed by Tom Helms (Ozone Policy and Strategies Group) and Leila Cook (State Measures and Conformity Group) entitled 1-Hour Ozone Maintenance Plans Containing Basic I/M Program provides clarification on how the CAA's anti-backsliding provisions apply under the 8-hour standard with regard to certain categories of vehicle inspection and maintenance (I/M) programs.
- October 3, 2002 Guidance Memo and Attachment, signed by Margo Oge, entitled "Considerations for State I/M Program Optimization" provides a list of questions and/or issues states should consider as they make choices about their existing and/or future I/M programs.
- EPA guidance on Model Year Exemption Policy (PDF) (2 pp, 9K, EPA420-S-99-007, December, 1999)
- The Calculation of I/M Waiver Adjusted for CPI (PDF) (2 pp, 8K, EPA420-B-99-011, December 1999) is the methodology that states should use to determine the minimum repair expenditure limit for waiver under 51.360 of the I/M rule.
Inspection and Maintenance (I/M) Procedures
The IM240 Transient I/M Dynamometer Driving Schedule and The Composite I/M Test Procedure (PDF) (EPA-AA-TSS-91-1, 18pp, 154K, January 1991)
IM240 Technical Guidance
- November 2000 Inspection/Maintenance Testing Lookup Tables, v 1.8.5
- Read Me File (TXT)(1 pg, 42 K) Free Viewers
- Data Format (TXT)(1 pg, 9 K) Free Viewers
- Lookup Table Data (EXE) (412 K) Free Viewers (downloadable, self-extracting into five data files)
- October 3, 2000 Final Report
- IM240 & Evap Technical Guidance (PDF) (113pp, 1.8M, EPA420-R-00-007, April, 2000)
- August 1998 IM240 and Evap Technical Guidance (EPA420-R-98-010, August 1998, replaces 3/98 draft revised guidance)
- Full Report (PDF) (112pp, 1.3M, EPA420-R-98-010, August 1998)
- June 1996 Draft Revised IM240 Technical Guidance: High-Tech I/M Test Procedures, Emission Standards, Quality Control Requirements, and Equipment Specifications: IM240 and Functional Evaporative System Tests (PDF) (87pp, 414K, EPA-AA-RSPD-IM-96-1, June 1996)
- July 1994: High Tech Inspection and Maintenance Tests (Procedures and Equipment) (PDF) (6pp, 66K, EPA400-F-93-005)
High-Tech Tests for High-Tech Vehicles
Acceleration Simulation Modes (ASM)
- Acceleration Simulation Mode Test Procedures, Emission Standards, Quality Control Requirements, and Equipment Specifications Final Technical Guidance (PDF) (57 pp, 1.1 MB, EPA420-B-04-011, July, 2004)
- June 26, 1996 Final ASM Test Procedure Documentation (PDF) (46 pp, 185 K, EPA-AA-RSPD-IM-96-2, July 1996)
- Evaluation of a Four-Mode Steady-State Test with Acceleration Simulation Modes (ASM) as an Alternative Enhanced I/M Test (May, 1993 Report).
- ASM Revised Draft Test Procedure
- Report and Appendices (PDF) (258 pp, 8.48 MB, EPA-AA-AQAB-93-01, May 11, 1993)
Contact: Dave Sosnowski at 734-214-4823 or dave.sosnowski@epa.gov