US EPA - Exempt VOCs
VOCs exempt from smog regulation because of negligible photochemical reactivity
VOCs which are exempt from smog regulation due to the EPA determination that they have negligible...
VOCs which are exempt from smog regulation due to the EPA determination that they have negligible photochemical reactivity. This does not mean they are not harmful to human health or the environment, only that they are not expected to take part in smog formation. Some of the exempted chemicals are harmful to human health.
The US EPA list of exempted chemicals is formally listed in Code of Federal Regulations (CFR) Title 40, Section 51.100 , subsection (s)(1)