Although OSHA does not specifically regulate TEG and PG, The Entertainment Services and Technology Association (ESTA) and The American National Standards Institute (ANSI) recommend exposure limits of:
10mg per cubic meter (light to moderate haze)
8-hr average exposure time
40mg per cubic meter (heavy haze)
peak exposure limit
These limits have an enormous safety factor baked in. According to the EPA, mammalian tests “showed a lack of systemic toxicity at doses in excess of 1000mg per cubic meter. Chronic exposure of experimental animals to TEG at doses equivalent to or in excess of that dose for such studies has shown the chemical to be without adverse toxic effects.”