Ask the Expert Question-and-Answer Archive

by Ron Joseph

May, 2004

Exempt Solvents

Q. What is an exempt solvent?

A. Thank you for your email. An exempt solvent is a volatile organic compound that does not participate in an atmospheric photochemical reaction to form smog. It can be an organic solvent but it takes so long to react with nitrogen oxides (NOx) in the presence of sunlight that the EPA considers its reactivity to be negligible. Only a handful of exempt solvents are approved for use in paints and coatings and these include acetone, methyl acetate, PCBTF (Oxsol 100), volatile methyl siloxanes.

The definition of exempt solvents can be found in 40 CFR 51.100(s)

I hope this helps you.

Best wishes,

Ron Joseph