A flammable liquid is any liquid with a flash point at or below a certain threshold, as defined by some governing body.
The Occupational Safety and Health Administration (OSHA) of the United States Department of Labor defines a liquid as flammable if it has a flash point at or below 199.4° F (93° C).[1] Prior to bringing regulations in line with the United Nations Globally Harmonized System of Classification and Labeling of Chemicals (GHS) in 2012, OSHA considered flammable liquids to be those with a flash point below 100° F (37.8° C). Those with flash points above 100° F and below 200° F (93.3° C) were classified as combustible liquids.[2][3] Studies show that the actual measure of a liquids flammability, its flash point, is dependent on altitude.[4]
Categorization
editBoth OSHA and GHS further divide flammable liquids into 4 categories:
- Category I flammable liquids are those with boiling points ≤ 95° F (35° C) and flash points < 73° F (23° C)[1][5]
- Category II flammable liquids are those with boiling points > 95° F and flash points < 73° F[1][5]
- Category III flammable liquids are those with flash points > 73° F and ≤ 140° F (60° C)[1][5]
- Category IV flammable liquids are those with flash points > 140° F and ≤ 199.4°F[1][5]
These categorizations are dependent upon a set altitude and atmospheric pressure, as both boiling point and flash point change with changes in pressure.[4][6]
Labeling
editBoth GHS and OSHA require the labeling of flammable liquids, on containers and safety data sheets, as follows:[3][5]
Category I | Category II | Category III | Category IV | |
---|---|---|---|---|
Symbol | Flame | Flame | Flame | none |
Signal Word | Danger | Danger | Warning | Warning |
Hazard Statement | Extremely flammable liquid and vapour | Highly flammable liquid and vapor | Flammable liquid and vapour | Combustible liquid |
References
edit- ^ a b c d e "1910.106 - Flammable liquids. | Occupational Safety and Health Administration". www.osha.gov. Retrieved 2019-03-06.
- ^ "But It Wasn't Flammable Before! GHS Changed the Meaning of 'Flammable Liquids'". EHS Daily Advisor. 2015-09-23. Retrieved 2019-03-08.
- ^ a b "HCS/HazCom 2012 Final Rule & Appendices | Occupational Safety and Health Administration". www.osha.gov. Retrieved 2019-03-08.
- ^ a b Ding, Chao, et al. “Experimental Study of the Flash Point of Flammable Liquids under Different Altitudes in Tibet Plateau.” Fire & Materials, vol. 38, no. 2, Mar. 2014, pp. 241–246. EBSCOhost, doi:10.1002/fam.2177.
- ^ a b c d e Globally harmonized system of classification and labelling of chemicals (GHS). United Nations. Economic Commission for Europe. Secretariat. (Seventh revised edition ed.). New York. ISBN 9789211171310. OCLC 994197992.
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has extra text (help)CS1 maint: others (link) - ^ "Standard Temperature and Pressure". www.kentchemistry.com. Retrieved 2019-03-11.