Cold starts and warm-up idling by morning commuters was implicated as the cause of the elevated CO levels found in some neighborhoods. A third study was conducted during the winter of 1998-99. This objective of this study, which was a joint effort by the Municipality, Alaska Department of Environmental Conservation and the Fairbanks North Star Borough, was to quantify the amount of CO produced by vehicles during cold start and subsequent warm-up. Prior to this study, very little information was available on vehicle emission rates during cold start. Preliminary results from the over 150 vehicles tested in Anchorage and Fairbanks indicate that emissions during the cold start phase are very significant.
Results also suggest that using engine block heaters can cut emission rates by about two-thirds.