Re: "Focus on safety, not AirCare," letter to the editor, Wednesday, March 7.

I'd like to take this opportunity to clarify some remarks raised by M. Guenther's letter concerning AirCare.

The AirCare program has acknowledged and credited the effectiveness of new vehicle emissions technology in all of our published reports. We have also recognized the improved durability of this technology by exempting vehicles from AirCare inspection until they are seven model years old.

In spite of these technological improvements, emission-system components can, and still do, fail. This is confirmed by the more than 40,000 vehicles that failed an AirCare inspection in 2011 - more than half of them for the first time.

By systematically identifying and correcting emission-related problems as they develop, the vehicle fleet runs cleaner and contributes less pollution to our air. Having AirCare in place has significantly reduced vehicle emissions and helped to improve the air quality in this region. This is not propaganda but a fact supported by numerous independent audits of the program. I suggest Mr. Guenther and other NOW readers visit our website at www.aircare.ca to read these reports on the benefits of AirCare.

Dave Gourley, P.Eng General Manager, AirCare