16VAC25-70-100:1. APPENDIX A. Concentrations at which some common substances exhibit immediately dangerous to life or health (IDLH) effects.
APPENDIX A.
Concentrations at which some common substances exhibit immediately dangerous to life or health (IDLH) effects.
Appendix A is a non-mandatory appendix. According to The National Institute for Occupational Safety and Health (NIOSH) the levels listed below represent a maximum concentration from which one could escape within 30 minutes without any escape-impairing symptoms or any irreversible health effects. These levels were published by NIOSH in September 1985 and are subject to frequent change. This list is not meant to be all inclusive but rather is meant to list some of the more frequently encountered chemicals in confined spaces.
| Appendix A | |
| CHEMICAL NAME | IDLH LEVELS* |
| Ammonia | 500 ppm |
| Benzene | 2,000 ppm |
| Butadiene | 20,000 ppm |
| 2 - Butanone | 3,000 ppm |
| Carbon dioxide | 50,000 ppm |
| Carbon monoxide | 1,500 ppm |
| Carbon tetrachloride | 300 ppm |
| Chlorine | 25 ppm |
| Chlorobromomethane | 5,000 ppm |
| Chloroform | 1,000 ppm |
| Cresol | 250 ppm |
| Cyclohexane | 10,000 ppm |
| Dichlorodifluoromethane | 50,000 ppm |
| Dichloromonofluoromethane | 50,000 ppm |
| Ethyl acetate | 10,000 ppm |
| Fluorotrichloromethane | 10,000 ppm |
| Heptane | 4,250 ppm |
| Hexane | 5,000 ppm |
| 2 - Hexanone | 5,000 ppm |
| Hydrogen chloride | 100 ppm |
| Hydrogen sulfide | 300 ppm |
| Isopropyl alcohol | 20,000 ppm |
| Liquefied petroleum gas | 19,000 ppm |
| Methyl alcohol | 25,000 ppm |
| Methyl cellosolve | 2,000 ppm |
| Methyl cellosolve acetate | 4,500 ppm |
| Methyl chloroform | 1,000 ppm |
| Methylene chloride | 5,000 ppm |
| Nitric oxide | 100 ppm |
| Nitrogen dioxide | 50 ppm |
| Octane | 3,750 ppm |
| Ozone | 10 ppm |
| Pentane | 5,000 ppm |
| Petroleum distillates mixture | 10,000 ppm |
| Phenol | 100 ppm |
| Phosgene | 2 ppm |
| Propane | 20,000 ppm |
| Sodium hydroxide | 200 mg/M3 |
| Stoddard solvent | 5,000 ppm |
| Styrene | 5,000 ppm |
| Sulfur dioxide | 100 ppm |
| 1, 1, 2, 2, - Tetrachloro-1, 2 - difluroethane | 15,000 ppm |
| Toluene | 2,000 ppm |
| Toluene-2, 4-diisocyanate | 10 ppm |
| Trifluoromonobromomethane | 50,000 ppm |
| Turpentine | 1,900 ppm |
| Xylene | 10,000 ppm |
| *Reference NIOSH/OSHA Pocket Guide to Chemical Hazards DHEW (NIOSH) Publication No. 78-210 | |
Statutory Authority
§ 40.1-22(5) of the Code of Virginia.
Historical Notes
Derived from VR425-02-30, eff. November 15, 1987; amended, eff. July 1, 1988.