| Organization | Standard | Reference | 
|---|
| Mine Safety and Health Administration (MSHA) STANDARD-air | time-weighted average 1000 ppm (1800 mg/m3) | DTLVS* 3,146,1971 | 
| Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV; |  |  | 
| Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV |  |  | 
| Occupational Exposure Limit-AUSTRALIA | time-weighted average 1000 ppm (1800 mg/m3), JUL2008 |  | 
| Occupational Exposure Limit-BELGIUM | time-weighted average 1000 ppm (1826 mg/m3), MAR2002 |  | 
| Occupational Exposure Limit-KOREA | time-weighted average 1000 ppm (1800 mg/m3), 2006 |  | 
| Occupational Exposure Limit-MEXICO | time-weighted average 1000 ppm (1800 mg/m3);short term exposure limit 1250 ppm, 2004 |  | 
| Occupational Exposure Limit-NEW ZEALAND | time-weighted average 1000 ppm (1800 mg/m3), JAN2002 |  | 
| Occupational Exposure Limit-THE NETHERLANDS | MAC-TGG 1800 mg/m3, 2003 |  | 
| Occupational Exposure Limit-THE PHILIPPINES | time-weighted average 1000 ppm (1800 mg/m3), JAN1993 |  | 
| Occupational Exposure Limit-TURKEY | time-weighted average 1000 ppm (1800 mg/m3), JAN1993 |  | 
| Occupational Exposure Limit-UNITED KINGDOM | time-weighted average 1000 ppm (1750 mg/m3);short term exposure limit 1250 ppm (2180 mg/m3), OCT2007 |  | 
| Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction) | 8H time-weighted average 1000 ppm (1800 mg/m3) | CFRGBR 29,1926.55,1994 | 
| Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors) | 8H time-weighted average 1000 ppm (1800 mg/m3) | CFRGBR 41,50-204.50,1994 | 
| Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry) | 8H time-weighted average 1000 ppm (1800 mg/m3) | CFRGBR 29,1910.1000,1994 | 
| Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards) | 8H time-weighted average 1000 ppm (1800 mg/m3) | CFRGBR 29,1915.1000,1993 |