You guys, down there are voting on a red herring.
Just what percentage of the cars on the road down there are over 30 y/o ? . . just what percentage of polution do they contribute?
Seems to me, that worrying about 30 y/o cars being up-to-snuff, (testing) is like worrying about whether farmer-John is keeping his cows washed & brushed (to keep the flys off) while they fart & crap all day long.
Get this;
"Only 2 percent of the vehicles on California's roads are diesel-powered and yet, diesel vehicles account for 31% of the total smog forming oxides of nitrogen (NOx) and 79% of the total particulate matter (PM) emissions produced by on-road vehicles. "
(source)