Types of Inspections

Depending upon the age and type of vehicle, the following tests are performed:

OBD is a non-driving test in which the vehicles on-board computer is connected to a computer at the Air Care Colorado facility that accesses various information.  This includes details about the "Check Engine" light, other dashboard indicators and codes that help determine emissions-related problems for quicker repair and improved performance.

The I/M240 is the "treadmill" test most commonly identified with emissions inspections in the Denver-metropolitan area and the North Front Range.  Vehicles are driven on a device known as a dynamometer that simulates a four-minute driving cycle under a variety of conditions (uphill, downhill, acceleration and more) to evaluate emissions.

This is the original type of test that evaluates emissions at two different idle speeds. It is used as part of the inspection for 1981-and-older vehicles.

Sometimes tests may not be performed as part of the overall inspection because the vehicles configuration or onboard computer are preventing communication with the equipment at the Air Care Colorado facility.  Vehicles also may be selected randomly for on-going program studies that are continually used by the State of Colorado for quality assurance purposes to evaluate overall program effectiveness.

A properly functioning gas cap is an essential part of the emissions control system of every vehicle.  Missing or leaking gas caps will cause vehicles to fail the emissions inspection.  A full retest is required if a vehicle fails an initial inspection for a missing or defective gas cap because the gas cap affects the overall emissions control capability.  The vehicle must be inspected completely with the new gas cap in place in order to be properly evaluated.

RapidScreen is an alternative to the inspection at an Air Care Colorado facility first used right here in Colorado!  RapidScreen utilizes data collection units placed roadside that can evaluate emissions as a vehicle drives by.  It is an alternative to the standard inspection and is used to identify vehicles that are operated exceptionally cleanly.  Please visit the RapidScreen page on this website for more information.