At the end of this module, you will be able to:
- Define the terms "flash point," "boiling point," "autoignition temperature," "explosive limits"
- Differentiate between "combustibles" and "flammables"
- Describe how flammables and combustibles are classified or categorized
- Describe OSHA's HazCom Standard workplace requirements for hazardous chemicals
- Describe how flammability is indicated on chemical labels
- Identify the characteristics of flammables which make them especially hazardous
- List storage and handling best practices for flammable liquids
The following key questions are answered in this module:
What is the difference between combustible liquids and flammable liquids?
Combustible liquids and flammable liquids have different "flash points" ("flash point" is the lowest temperature at which a liquid gives off enough vapor to ignite in air if an ignition source is present). Flammables have lower flash points, and are therefore more hazardous, than combustibles.
What is the Hazardous Communication, or HazCom, standard?
OSHA created the HazCom Standard to protect U.S. workers from chemical hazards. It requires information on the identities and hazards of workplace chemicals to be available and understandable to workers.
What are upper and lower "explosive limits"?
Upper and lower "explosive limits" define the concentration range of vapor in air that will burn or explode if an ignition source is present.
What are NFPA specifications for inside storage rooms that are used to store flammable liquids?
They must be equipped with liquid-tight raised door sills or open-grated trenches, fire doors, liquid-tight floor-to-wall joints, and window protection. They must also meet the fire resistive rating for their use.
How often should inventory be taken for chemicals at a worksite?
It is best to maintain an accurate inventory at all times by updating it whenever a chemical is added to or removed from a site.
Below is a transcript of the video sample provided for this module:
A material's autoignition temperature (or AIT) is the temperature at which, in the presence of oxygen, the material can self-ignite without an obvious ignition source. It is completely independent of flash point. Most common flammables have AITs above 570 °F (300 °C), but a few are lower. AITs are included in SDSs and can be used to evaluate the hazard level present when a liquid is exposed to elevated temperatures. The vapors from some solvents can be ignited by items like hot steam pipes, and serious accidents have occurred when low-AIT solvents were heated in solvent-evaporating ovens.
Use the additional resources and links below to learn more about this topic:
- Occupational Safety and Health Administration (OSHA) – www.osha.gov
- OSHA Standards - https://www.osha.gov/pls/oshaweb/owastand.display_standard_group?p_toc_level=1&p_part_number=1910
- National Fire Protection Association (NFPA) - http://www.nfpa.org/
- NFPA 30 Standard - http://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards?mode=code&code=30