Safely storing flammable liquids

The following provides an overview on container and portable tank storage under the OSHA regulation on flammable liquids at §1910.106, paragraph (b), as well as incidental use at industrial plants under paragraph (e).

Paragraph (b) applies to the storage of flammable liquids (including flammable aerosols) in containers up to 60 gallons and portable tanks under 660 gallons. It does not apply to bulk plants, service stations, refineries, chemical plants, or distilleries. It also does not apply to flammable paints, oils, varnishes, and similar mixtures used for maintenance when not kept for more than 30 days.

Containers and cabinets

Among other things, OSHA requires storing flammable liquids only in approved containers or tanks, describing the maximum capacity based on the class of the liquid and the container type (glass, metal, etc.). Fire control devices, such as portable fire extinguishers, must be available where flammable liquids are stored.

When using storage cabinets, not more than 60 gallons of Category 1, 2, or 3 liquids, nor more than 120 gallons of Category 4 liquids may be stored in a cabinet. Cabinets must be labeled, “Flammable – Keep Fire Away.”

Cabinets meeting OSHA’s requirements can be purchased, but if more storage capacity is needed, employers may need to construct a storage room. The provisions for inside storage rooms are much more extensive, as detailed in the regulation.

Incidental use in industrial plants

Since not every industrial facility relies on chemical reactions, OSHA includes provisions for plants where the use of flammable liquids is incidental to the business, such as flammable finishing materials used in furniture manufacturing.

As you’d expect, flammable liquids must still be stored in tanks or closed containers. The quantity of liquid that may be located outside of an storage room or storage cabinet in a building (or in any one fire area of a building) must not exceed:

• 25 gallons of Category 1 flammable liquids in containers
• 120 gallons of Category 2, 3, or 4 flammable liquids in containers
• 660 gallons of Category 2, 3, or 4 flammable liquids in a single portable tank

The regulation has far more detail than could be provided here, but at a minimum, employers need to know the quantity of flammable liquids, the class of those liquids, and the acceptable containers or methods for storing them.