Page 54 - OHS, JulyAugust 2023

FC A AH L L LM This claim that combustible liquids no longer exist simply isn’t true. E P PI C RAO LT ESC AT FI E OT NY National Fire Protection Association (NFPA) still uses the same classes of flammable and combustible liquids in its NFPA 30 Standard, upon which the previous HazCom Standard definitions were based. However, it is important to note that they also have recently changed some of the terminology. To reduce confusion caused by the various definitions and the perception that combustible liquids are somehow less hazardous, the NFPA has switched to the term ignitible liquids. Even so, the full term is ignitible (flammable and combustible) liquid, as the categories within the ignitible umbrella include delineation between flammable and combustible liquids. The Department of Transportation under 49 CFR 173.120 still defines liquids as either combustible or flammable (except using 140 degrees Fahrenheit as the dividing flashpoint — see figure 3). The Environmental Protection Agency (EPA) has used the term ignitable liquid for decades to describe any liquid with a flashpoint below 140 degrees Fahrenheit. The term ignitable (with a slightly different spelling than NFPA) is used because it also describes other hazardous wastes such as solids and gases. The point is, just because GHS utilizes four categories of flammable liquids does not mean that the term combustible — or other terms such as ignitable — no longer exists or shouldn’t be understood by a safety professional. To be sure, there are definite advantages to simply having different categories of flammable liquids under the GHS. Just as the NFPA recognized, the terms combustible and flammable have caused confusion and misunderstanding. Obviously, I wasn’t the only individual to have a hazy (or completely wrong) understanding of the differences between flammable and combustible liquids. In addition, having different terms for the liquids may give the wrong impression that somehow combustible liquids are safer than flammable liquids. As an example of how wrong this notion can be, kerosene would be considered a combustible liquid under the older definition. But with a flashpoint barely over that 100 degrees Fahrenheit dividing line, it can easily be heated — just by the weather in some cases — to a point that it is more dangerous and ignitable than gasoline is at room temperature. So, defining all these liquids as varying categories of flammable liquids may communicate the hazards more clearly, which after all is the whole point of the HazCom Standard. So why make an issue about the use of the term combustible liquids when it isn’t even used by OSHA? First, as a safety professional, you are likely to have to reference other standards, such as those used by the DOT, NFPA and EPA. And second, if you believe that the HazCom Standard under GHS doesn’t use the term combustible liquid, you’d be wrong again. Yes, they have reclassifified their defifinitions into four categories of flflammable liquids, but if you dig a little deeper, you’ll fifind an interesting little tidbit: Under 29 CFR 1910.1200 Appendix C.4.19, Category 4 flammable liquids must carry a Hazard Statement that reads: “Combustible liquid!” (This change of definition actually puts OSHA’s terminology more in sync with the DOT — placing combustible liquids above the 140-degree-Fahrenheit flashpoint level, see figure 3 — which interestingly enough, was changed years earlier from the NFPA 30 Standard to align with UN definitions to facilitate international trade.) Figure 3: DOT 49 CFR 173.120 Flammable and Combustible Liquids So, OSHA not only still uses the term combustible liquid, the regulations require it to still be used on labels under the newer HazCom Standard. Contrary to the claims, combustible liquids not only still exist — it appears they are here to stay. Figures The new GHS definitions of flammable liquids (found at 29 CFR 1910.106) are similar but simpler and easier to understand than the old HazCom definitions of flammable and combustible liquids based upon the NFPA 30 Standard. Class IA and IB liquids become Category 1 and 2 liquids respectively (the temperatures are based upon degrees Celsius rather than Fahrenheit in GHS, but are essentially unchanged). Class 1C and Class II liquids are combined into Category 3 liquids. Class IIIA liquids are reclassified as Category 4 liquids. There is no obvious delineation between flammable and combustible liquids anymore. Also, Class IIIB combustible liquids aren’t categorized under the new system, although any flammable liquid with a flashpoint greater than 200 degrees Fahrenheit still must be cared for with the same precautions as a Category 4 flammable liquid if it is heated to within 30 degrees Fahrenheit of its flashpoint. Tim Carrico is an operator and union safety rep at the largest pulp and paper mill on the West Coast of the United States. He currently serves as a Director of the Washington State Governor’s Industrial Safety and Health Advisory Board, representing labor for the pulp, paper, and forest products industry across the state. Tim holds a degree in Occupational Safety and Health from Columbia Southern University and enjoys shar- ing his knowledge and passion at safety conferences across the country. REFERENCES 1. www.osha.gov/top10citedstandards 2. www.osha.gov/sites/default/files/publications/OSHA3636.pdf 3. Asfahl, C. R., Rieske, D. W. (2010). Industrial safety and health management, sixth edition. 4. www.nfpa.org/-/media/files/code-or-topic-fact-sheets/NFPA_30_Fact_ Sheet_2021.ashx 5. Haight, J. M. (2013) Hazardous Material management and hazard communication, second edition. 54 Occupational Health & Safety | JULY/AUGUST 2023 www.ohsonline.com