Program Basics

General Information

OBD inspections are performed annually on light-duty passenger vehicles (8500 GVWR and less) whose model year is 20 years old and newer. The program enables licensed inspection stations to perform OBD inspections and allows the State to comply with Environmental Protection Agency (EPA) regulations. It also provides automated collection of Safety Inspection results.

On-board diagnostics, or OBD, systems were developed to help repair technicians identify problems associated with the computerized engine systems of modern vehicles. Federal law requires states that do not meet federal air quality standards to implement an OBD inspection program to ensure that emissions control equipment is operating correctly. Part of the OBD inspection includes verifying that the "Check Engine" or "Service Engine Soon" light is not illuminated on the vehicle's dashboard.

Modern vehicles emit less air pollution than older vehicles due to new engine management technology and emission control equipment, but these cars are only cleaner if all emission control systems are operating properly. The OBD system can often detect a vehicle malfunction before the driver becomes aware of the problem. Early detection and repair of malfunctions will result in fewer emissions. In addition, early repair of minor problems may prevent more significant and more expensive engine problems that could develop if left undetected.

Stickering Process

The New Hampshire vehicle inspection process includes the following windshield sticker-related elements:

  • Safety Pass & OBD Pass: The vehicle receives a sticker that expires in owner’s birth month.
  • Safety Pass & OBD Reject: The vehicle receives a sticker with a 60-day expiration date.
  • Safety Reject & OBD Pass: No Change to the sticker that is on the windshield.
  • Safety Reject & OBD Reject: No Change to the sticker that is on the windshield.

Station Information

In order to become a licensed NHOST inspection station, you must complete an NHOST enrollment package.

The package includes a Station Agreement and Enrollment Form, as well as a Direct Payment Authorization form. The package (including the Station Agreement, Direct Payment Authorization, and a voided check) needs to be completed by the station and returned to us.

To receive a package, go to the Enrollment page of this site or call us at 1-800-383-4124 to request one be faxed or mailed to you.

Completion of the enrollment package will authorize you to receive NHOST equipment, and allow your continued participation in the inspection program.

Mechanic Information

All participants of the Safety Inspection program need to be certified mechanics prior to performing OBD inspections.

A Computer Based Training program (CBT) will allow mechanics to complete training at their own workplace, right on their shop's NHOST System. The CBT will cover both OBD inspections and use of the NHOST unit. A take-home CD is also available.

The certification test is done by the mechanic on the NHOST unit. Once the mechanic passes, then he or she is immediately authorized to use the NHOST system.

The CBT software will remain on the unit, and can be accessed any time by the mechanics if they need to refresh their knowledge of a particular NHOST feature.