In Virginia (if anyone is interested) it is triggered by population in each county. In 1990, I moved from Fairfax County west to Loudoun County, for a variety of reasons, one being no emissions testing in Loudoun. Joke was on me, though, two years later Loudouns population hit the trigger, and emissions testing started. In 1999 I moved to the far western edge of Loudoun to escape the overcrowding and crime in the eastern part of the county where I lived. Joke was on me again, because from 2002-2007 thousands of new homes were built in the western end. Now just 5 miles west of me is another county, Clarke, and it has no emissions testing and is still fairly rural. I wanted to move there in '99, but Clarke's school system sucks, and that was a consideration for me. Clarke's taxes are lower too, and I usually head over there to buy gas, as it runs about .15 cents less a gallon than in my county. One other way to avoid emissions testing in VA. is to register the vehicle as antique (25y
rs. or older) and then it is exempt from both emissions and safety inspection.     Jeff