Not an expert on emissions; others on this list are.  From what I've been
reading, some states have adopted the CA standard while others use the US
standard.  There may be some variations in testing, etc. but there seem to
be only two actual standards, and those may only relate to new vehicles.

I have been hearing for a long time how "dirty" our vans are, but looking up
the CA and US standards for LDT2 (the category our vans would fall into),
and the emissions readings posted by David B earlier today (which coincide
with my own readings), we're not far off the fleet readings for new light
trucks.

Could I have misinterpreted the EPA charts?  Heck yes, but I don't think so.
If our vans are tuned correctly, they seem to be pretty darned clean.  Now,
if you're comparing apples and oranges and comparing our vans to the new
ultra clean burn vehicles, which are mostly passenger vehicles, then, sure,
they are dirty, but compared to current light trucks/small vans, they seem
to hold their own.

If anyone has actual numbers to prove otherwise, let us all know, but
remember to keep your fruits in a row!

Karl Wolz

Don't know 'where' you are talking about, but I believe emission limits have
gotten tighter and tighter a bit at a time,
year by year, for a long time.  Thinking of Ca. mainly.  Can't say about
other states. Some are quite lax.