nie brzmi to jak poemat, ale oddaje sens - chyba że kontekst, który pominąłeś, wskazuje na inne znaczenie tego "less"

What are VOC-exempt solvents?
EPA regulations include a list of compounds that are explicitly exempted from regulation as VOCs , even though they are "compounds of carbon." These include a short list of compounds such as carbon monoxide and carbon dioxide that historically have not been regulated as VOCs, and a longer list of compounds that EPA has classified as "negligibly reactive." Negligibly reactive compounds are compounds that, based on scientific studies, have been found "not to contribute appreciably to ozone formation." This list of compounds (often referred to as "VOC-exempt compounds") is established and modified by regulation. The list of exempt compounds is found at 40 C.F.R. 51.100(s).
http://www.americanchemistry.com/s_acc/sec_solvents.asp?CID=...

Exempt Solvent
Specific organic compounds not subject to requirements of regulation because they are deemed by EPA to be of negligible photochemical reactivity.
http://www.caslab.com/Exempt_Solvent_Meaning/

Q: What is an exempt solvent?
A: 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)

http://ronjoseph.com/Q&A/I1101_exempt_solvents.htm

Volatile Organic Compounds (VOC)
Volatile Weight X% Less (Water and) Federally Exempt Solvents
http://je.pl/f498

--------------------------------------------------
Note added at 1 day1 hr (2009-03-12 20:24:50 GMT)
--------------------------------------------------

Ewentualnie:
- nie licząc rozpuszczalników niepodlegających przepisom/regulacjom federalnym

--------------------------------------------------
Note added at 156 days (2009-08-14 22:10:40 GMT)
--------------------------------------------------

nie licząc rozpuszczalników niepodlegających przepisom/regulacjom federalnym