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Vehicle Emissions Inspection and Maintenance (I/M): Tampering, Warranty, State Websites and Program Evaluations

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Tampering and Warranty Coverage

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State Websites

The following links exit the site Exit

State Website 
AZ http://www.myazcar.com/
CA http://www.smogcheck.ca.gov/
CT http://ctemissions.com/
CO https://www.colorado.gov/cdphe/categories/services-and-information/environment/air-quality/motor-vehicle-emissions
DC https://dmv.dc.gov/service/vehicle-inspections
DE https://dnrec.alpha.delaware.gov/air/mobile-sources/inspection-maintenance/
GA http://www.cleanairforce.com/
ID Ada County: http://www.emissiontest.org/
Canyon County: http://www.idahovip.org/
IL https://www2.illinois.gov/epa/topics/air-quality/mobile-sources/Pages/vehicle-emissions-testing.aspx
IN https://www.in.gov/idem/airquality/2333.htm
LA https://deq.louisiana.gov/page/motor-vehicle-inspection-and-maintenance
ME https://www.maine.gov/dep/air/mobile/enhancedautoinsp.html
MD https://mde.maryland.gov/programs/air/mobilesources/pages/veip.aspx
MA https://www.mavehiclecheck.com/
MO http://www.dnr.mo.gov/gatewayvip/
NC https://deq.nc.gov/about/divisions/air-quality/motor-vehicles-air-quality/inspection-maintenance-program
NV http://nevadadmv.state.nv.us/emission.htm
NH http://nhinspect.com/
NJ https://www.state.nj.us/mvc/
NM http://www.mvd.newmexico.gov/emission-testing.aspx
NY http://www.dec.ny.gov/chemical/8391.html
OH https://epa.ohio.gov/dapc/mobile
OR https://www.oregon.gov/deq/Vehicle-Inspection/Pages/default.aspx
PA http://www.drivecleanpa.state.pa.us/
RI https://www.riinspection.org/
TN https://www.tn.gov/environment/program-areas/apc-air-pollution-control-home/apc/vehicle-inspection-program1.html
TX https://www.tceq.texas.gov/airquality/mobilesource/im.html
UT http://dmv.utah.gov/register/inspections
VT https://dec.vermont.gov/air-quality/mobile-sources/vehicle-inspections
VA https://www.deq.virginia.gov/air/vehicle-emissions-air-check
WA http://www.ecy.wa.gov/programs/air/cars/Automotive_Pages.htm
WI http://www.wisconsinvip.org/WivipPublic/  

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Program Evaluations

  • July 2004, Guidance on the Use of Remote Sensing for Evaluation of I/M Program Performance (PDF) (63 pp, 795K, EPA420-B-04-010, July 2004)
    This document is the finalized version of the July 2001 draft.  It is intended to provide states with technical guidance on how to perform I/M program evaluations using RSD technology.  Note:  EPA is currently reviewing one set of comments received on this document that were inadvertently overlooked.  We anticipate incorporating any new changes in the Fall of 2002.
  • August 2001, Guidance on the Use of in-Program Data for Evaluation of Program Performance (PDF) (90pp, 2.7M, EPA420-P-01-003, August 2001)
    The draft guidance document is intended to provide states with technical guidance on how to perform I/M program evaluations using in-program data.  Comments were accepted until November 12, 2001.
  • July 2001, EPA Equipment Audit Guidelines
    These guidelines should be used by states as a comprehensive tool for auditing I/M tailpipe testing equipment.
  • July 2001, Audit Forms
    The forms are to be used with the Equipment Audit Guidelines.
  • September 2000, Methodology used for Calculating VMT
    The document shows the VMT calculation methodologies used by CARB and can be a useful resource for other states needing to develop VMT calculation methodologies.
  • June 2000, Smog Check Station Performance
    The report was contracted by BAR and is based on Roadside test results and was used to evaluate station performance in the SMOG Check II Program.
  • February 2000, Roadside Inspection Program in California
    The report summarizes the roadside inspection program in California and is a good resource for states wishing to conduct their own roadside inspections.
  • October 30, 1998 METT Memorandum (PDF)(13 pp, 84 K, EPA420-S-98-015, October 1999)
    EPA memo outlining acceptable methods for I/M program evaluations.  The memo was noncommittal on the issue of using Remote Sensing as EPA felt additional work was needed to fully understand the benefits and disadvantages of the technique.  Toward that end, EPA has been working with the Coordinating Research Council Remote Sensing group to address the Agency's concerns.

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