Gasoline engines emit exhaust that contains hydrocarbons, carbon dioxide, carbon monoxide and oxides of nitrogen. Emission control technology has developed to minimize these emissions, but older vehicles or vehicles that are not properly serviced may emit excessively high levels of these pollutants. To address the serious air quality problems caused by the over one million light duty vehicles operating within the lower mainland, the B.C. Ministry of the Environment and the Greater Vancouver Regional District introduced the Motor Vehicle Emissions Inspection and Maintenance Program, AirCare in 1992. Other regions of BC have not had an AirCare program because the impact of motor vehicle pollution on their air quality has not, thus far, been considered to be as severe.
Under the original AirCare program, almost alllight-duty vehicles were required to be tested, prior to license and insurance renewal, to ensure that their emission levels were within the allowable Canadian standards. In its first 12 years of operation (1992–2004) the AirCare program found one in three vehicles to be faulty and in need of repair. As test patterns were established, exemptions developed for newer vehicles to the point where, beginning January 1, 2007, the testing exemption for newer model years will increase from 4 years to 7 years. As well, the test will change to include using the on-board diagnostic system on 1998 and newer vehicles to test the performance of their emission control system.
These changes will reduce the number of vehicles visiting AirCare stations in 2007, when the program expects to conduct just over 500,000 tests. In 2011 this number is expected to fall further to 491,000 (This compares to the 1.2 million tests conducted in 1999.) By 2011 it is expected that the AirCare program will wind up altogether.
Vehicles that fail an AirCare tailpipe test must be repaired so that their emissions are restored to normal levels or be retired from service. AirCare calculates that emissions from the light-duty vehicle fleet on January 1, 2005 were 71% lower than they would have been in 1992 and that while some of this is due to “fleet turnover” “an additional reduction of 29% can be attributed to AirCare.”
When it was first introduced, AirCare was a hot topic, criticized as “Just another tax”. Recently it is back in the news. It has been suggested that a vehicle may fail at one test centre and then pass at another a few hours later without having the vehicle repaired in the interim. If there is any truth to this, a possible explanation is that the vehicle may have warmed up masking the problem originally detected.
That different test centres have different failure rates—but not different levels for passing or failing—is understandable. AirCare explained “The test equipment [in the various centres] is the same but the vehicles that come in are completely different, leading to different failure rates between centres.”
If AirCar winds up in 2011, this will mark the success of clean engine technology.