NFPA 30: Flammable & Combustible Liquids
NFPA 30 is the code for storing and handling flammable and combustible liquids, from gasoline and solvents to diesel and lubricating oil. Fire codes and insurers rely on it, and OSHA has its own liquid rule (1910.106). This page explains the main ideas in plain language.
- General Industry
- Construction
- Facility Managers
How liquids are classified
The classes depend on flash point: the lowest temperature at which a liquid gives off enough vapor to ignite. Vapors, not the liquid itself, burn.
| Group | Class | Flash point | Examples |
|---|---|---|---|
| Flammable | IA | Below 73°F, and boiling point below 100°F | Ethyl ether, some propellants |
| IB | Below 73°F, and boiling point at or above 100°F | Gasoline, many solvents | |
| IC | 73°F or higher, and below 100°F | Turpentine, some solvents and alcohols | |
| Combustible | II | 100°F or higher, below 140°F | Diesel, kerosene, some solvents |
| IIIA | 140°F or higher, below 200°F | Some heavy oils | |
| IIIB | 200°F or higher | Many lubricating and hydraulic oils |
Find the flash point and class on the container label and in Section 9 of the Safety Data Sheet. Hot liquids can act like a lower class when heated above their flash point. See Safety Data Sheets.
What NFPA 30 controls
- Containers and storage: the type and size of containers allowed, how much can be kept in a room or cabinet, and when a separate storage room or building is needed. For flammable liquids, OSHA’s cabinet limit is 60 gallons of Class I and II, or 120 gallons of Class III. See Chemical Storage & Compatibility.
- Dispensing and transfer: use approved safety cans and pumps, bonding and grounding, and avoid pouring from open buckets. See Static, Bonding & Grounding.
- Ignition sources: control smoking, open flames, hot surfaces, hot work and sparks near vapors. See Hot Work Permits.
- Ventilation in rooms where vapors may collect, since most flammable vapors are heavier than air and settle in low spots.
- Electrical equipment in vapor areas must be rated for the hazardous location. See Hidden Wiring.
- Fire protection: extinguishers, sprinklers and spill control for areas where liquids are stored. See NFPA 10.
Everyday safe handling
- Keep flammable liquids in approved safety cans and flammable storage cabinets, not in glass or food containers.
- Keep only what you need for the day near the work. Store the rest in a cabinet or storage room.
- Label every container, including transfer containers.
- Keep containers closed, and clean up spills right away. Put used rags in a covered metal can. See Oily Rags.
- Never use gasoline to clean tools or hands, and never use it to start a fire.
OSHA and NFPA 30
OSHA’s rule 1910.106 is based on earlier editions of NFPA 30 and sets the legal minimums for general industry. Construction has its own rules in 1926.152. NFPA 30 is updated more often and is usually more detailed, and fire marshals and insurers may require the current edition. Follow whichever is stricter, and ask your local authority.
Checklist for a liquid storage area
- Liquids identified by class; quantities within limits
- Approved cans and cabinets; doors closed
- No ignition sources; electrical equipment rated for the area
- Spill kit, extinguisher and eyewash close by
- Bonding and grounding used for transfers
Note: This is a summary, and class limits, quantities and requirements are more detailed in the standard and local fire code. Use the edition your jurisdiction has adopted.
Standards & references
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