I also found this one, but it's EU specific: https://osha.europa.eu/en/legislation/directives/28
I also found this one, but it's EU specific: https://osha.europa.eu/en/legislation/directives/28
I found this reference: https://www.ilo.org/global/topics/safety-and-health-at-work/areasofwork/chemical-safety-and-the-environment/WCMS_151534/lang--en/index.htm
Recommended or mandatory occupational exposure limits (OELs) have been developed in many countries for airborne exposure to gases, vapours and particulates. The most widely used limits, called threshold limit values (TLVs), are those issued in the United States of America by the American Conference of Governmental Industrial Hygienists (ACGIH).