This article is Part 3 of our “Quick Facts About Fire Hazards” series. Check out the posts on combustible dust and hot work. And stay tuned for info on equipment and machinery and electrical hazards.
Flammable liquids and gases are present in many industrial environments, particularly in chemical and other processing plants. Just like with combustible dust, when a liquid or gas ignites, the results can be catastrophic.
Here are a few things you should know about liquid and gas fire hazards.
What’s the difference between flammable and combustible?
If you read the safety literature, you’ve undoubtedly seen warnings about both flammable and combustible liquids and gases. Both types of materials are hazardous. But there are some differences you should be aware of.
- For liquids, the difference between flammable and combustible is the flashpoint. This is the lowest temperature at which a material gives off sufficient vapor to ignite. Note that the liquids themselves don’t burn — the vapor they give off does.
- A combustible liquid has a flashpoint above 100°F.
- A flammable liquid has a flashpoint below 100°F. Thus, these materials are more dangerous.
- The definition of a flammable gas is a little more complicated. For simplicity’s sake, we can say that it is a compressed gas that will ignite under the right circumstances (e.g., pressure conditions). A combustible gas is a gas that will burn when mixed with oxygen and ignited.
For more information, see this resource from the Government of Virginia and this one from the ISA.
What liquids and gases pose fire hazards?
Many liquids and gases used in industrial settings are flammable or combustible. The lists below identify the most common ones:
- Flammable and combustible liquids (North Carolina State University)
- Combustible gases (Industry Scientific)
How do you prevent flammable and combustible liquid and gas fires?
As with the other fire hazards, incident prevention requires a multi-pronged approach. For flammable materials, the key element of that approach is storage. This FAQ document provides an overview of NFPA 30: Flammable and Combustible Liquids Code, including storage requirements.
Did you find this content useful? Check out 5 Major Causes of Industrial Fires and Explosions.