With all the low-level auto emissions terms I've encountered since ordering a Prius (ULEV, SULEV, PZEV, AT-PZEV, ZEV), I was getting a bit confused. However, the fine folks at the California Environmental Protection Agency did a two page summary sheet on the terms, with a graphic comparing the levels. (For more details, go to their website at http://www.driveclean.ca.gov/) BTW, the '04 Prius is rated AT-PZEV. (Approximately 96% cleaner than the average 2003 model vehicle.)
Thanks bookrats! It's a very helpful document. I'm going to extract some of that info and put it in the Knowledge Base glossary, too.
