OSHA 29 CFR 1910.106

Q: What is the relationship between OSHA 1910.106 and NFPA 30?

OSHA 1910.106 is the federal legal requirement for flammable liquid storage. NFPA 30 is the industry consensus standard with more detailed and current guidance. Many local fire codes adopt NFPA 30 directly. Complying with NFPA 30 will meet or exceed 1910.106 requirements.

Flammable Liquids: Storage, Handling, and Use Requirements

Last updated: April 2, 2026

Overview

29 CFR 1910.106 is the federal OSHA standard for flammable and combustible liquids in general industry workplaces. It sits in Subpart H (Hazardous Materials) and covers how these liquids must be stored, handled, and used on the job.

The standard applies to any employer that stores, uses, or handles flammable liquids with a flash point below 200 degrees F. That includes solvents, paints, fuels, adhesives, cleaning agents, and many coatings. If you have a gallon of lacquer thinner sitting on a shelf, this standard applies to you.

1910.106 classifies liquids by flash point and boiling point into categories. Class I liquids (flash point below 100 degrees F) are the most dangerous and have the strictest rules. Class II and IIIA liquids (flash point between 100 and 200 degrees F) are combustible and have slightly relaxed requirements.

Class	Flash Point	Boiling Point	Examples
IA	Below 73 F	Below 100 F	Diethyl ether, pentane
IB	Below 73 F	At or above 100 F	Gasoline, acetone, toluene
IC	73 F to below 100 F	Any	Xylene, butanol, turpentine
II	100 F to below 140 F	Any	Diesel fuel, kerosene, some mineral spirits
IIIA	140 F to below 200 F	Any	Paint thinners, stoddard solvent

Container Types and Maximum Size Limits

1910.106 specifies the maximum allowable container size based on the container type and the liquid class. Using the wrong container for the wrong class is one of the most common violations.

Container Type	Class IA	Class IB	Class IC	Class II	Class IIIA
Glass or approved plastic	1 pt	1 qt	1 gal	1 gal	1 gal
Metal (other than DOT drums)	1 gal	5 gal	5 gal	5 gal	5 gal
Safety can	2 gal	5 gal	5 gal	5 gal	5 gal
Metal drum (DOT spec)	60 gal	60 gal	60 gal	60 gal	60 gal
Approved portable tank	660 gal	660 gal	660 gal	660 gal	660 gal

Safety cans allow larger quantities of Class IA liquids than standard metal containers because the spring-loaded lid and flame arrester reduce ignition risk. For the most hazardous liquids, a safety can is the only practical option for daily use.

Storage Cabinet Requirements

Flammable storage cabinets are the most common way to meet 1910.106 inside a building. The standard defines specific construction and capacity requirements.

Capacity limits

Maximum 60 gallons of Class I or Class II flammable liquids per cabinet
Maximum 120 gallons of Class III combustible liquids per cabinet
No more than three cabinets in a single fire area unless separated by 100 feet

Construction requirements

Double-wall 18-gauge steel construction with 1.5 inch air space between walls
Self-closing doors with a three-point latch
2-inch liquid-tight sill at the bottom to contain spills
FM or UL listed cabinets meet these requirements by default

Common misconception: OSHA does not require flammable storage cabinets to be ventilated. The standard says cabinet vent openings must remain closed unless the cabinet is actively ventilated with an approved system. Most fire marshals and FM/UL listings recommend keeping the vent plugs sealed. If your local fire code requires ventilation, it is a local requirement, not federal OSHA.

Inside Storage Room Requirements

When quantities exceed what cabinets can hold, 1910.106 requires a dedicated inside storage room. These rooms have significant construction and engineering controls.

Fire-rated construction

Total Quantity Stored	Fire Resistance Rating	Automatic Sprinklers
Up to 150 gal per room	1 hour	Not required
150 to 500 gal per room	2 hours	Not required
Over 500 gal per room	2 hours	Required

Ventilation

Inside storage rooms must have either gravity or mechanical ventilation that provides at least one cubic foot per minute of exhaust per square foot of floor area. The ventilation system must be on before anyone enters and must run continuously when the room is occupied.

Electrical classification

All electrical wiring and equipment in inside storage rooms must meet NFPA 70 (National Electrical Code) for classified locations. Typically this means Class I, Division 2 rated equipment. Standard light switches, outlets, and fixtures are not allowed. This is one of the most expensive requirements to retrofit.

A self-closing fire door rated for the wall it is in is required at every opening. The door sill must be raised or the floor pitched to contain spills inside the room. At least 4 inches of containment depth is typical.

Safety Can Requirements

1910.106 defines a "safety can" as an approved container of not more than 5 gallons capacity with a spring-closing lid and spout cover, designed to safely relieve internal pressure when exposed to fire. Only FM or UL listed cans qualify.

Required features

Spring-loaded lid that closes automatically when released
Flame arrester screen in the pour spout to prevent flashback
Pressure relief mechanism to vent safely in a fire (prevents explosion)
Self-closing pour spout
FM Approved or UL Listed marking (required for compliance)

When you transfer flammable liquids from one container to another, both containers must be bonded and grounded to prevent static discharge. This applies to safety cans too. A bonding wire from the can to the receiving container, and a grounding wire from one of them to an earth ground, is the standard setup.

A standard gas can from a hardware store is not a safety can. It lacks the flame arrester, the spring-loaded lid, and the pressure relief. Using one in a workplace to store flammable liquids is a citable OSHA violation.

Oily Waste Disposal

Rags, waste materials, and residues contaminated with flammable liquids are a major ignition source. Spontaneous combustion from oily rags is one of the leading causes of workplace fires.

Requirements

Oily waste must be stored in self-closing metal waste cans
Waste cans must be emptied daily or at the end of each shift
Contents must be disposed of properly, not left to accumulate
Waste cans should be FM or UL listed for oily waste disposal

NFPA 30 (Flammable and Combustible Liquids Code) provides additional guidance on waste handling that goes beyond what 1910.106 covers. Many facilities follow NFPA 30 as their primary reference since it is more detailed and is updated more frequently than the OSHA standard.

Warning: Oily rags from linseed oil, tung oil, and other drying oils can self-ignite in as little as 2 to 3 hours if crumpled up and left in a pile. A self-closing oily waste can is not optional for these materials.

Compliance Penalties

Flammable liquid storage violations are among the most commonly cited OSHA standards, especially in manufacturing, auto repair, and construction staging areas.

Classification	Max Penalty (2024)	Common Violations
Serious	Up to $16,550	No safety cans, exceeding cabinet limits, improper storage room
Other-than-serious	Up to $16,550	Missing labels, vent plugs removed without ventilation system
Willful / Repeated	Up to $165,514	Known hazards left uncorrected, repeated citations for same violations

Penalty amounts are adjusted annually for inflation. Actual penalties depend on employer size, good faith, violation history, and gravity of the hazard. Having the right equipment (safety cans, listed cabinets) already in place when the inspector arrives makes a significant difference in citation outcomes.

Frequently Asked Questions

Does OSHA require flammable storage cabinets to be ventilated?

No. OSHA 1910.106 states that cabinet vent openings shall be sealed with the bungs provided unless the cabinet is connected to an approved exhaust system. Ventilation is not required. This is one of the most common misconceptions about flammable storage.

How much flammable liquid can I store in one cabinet?

A single cabinet can hold up to 60 gallons of Class I or Class II flammable liquids, or up to 120 gallons of Class III combustible liquids. You can have up to three cabinets in the same fire area. Beyond three, cabinets must be separated by at least 100 feet.

What makes a safety can different from a regular gas can?

A safety can has a spring-loaded lid, a flame arrester in the pour spout, and a pressure relief mechanism. These features prevent flashback, contain vapors, and vent safely in a fire. A regular gas can has none of these. Using a standard gas can for workplace flammable liquid storage is a citable OSHA violation.

Do I need bonding and grounding when pouring from a safety can?

Yes. When transferring flammable liquids between containers, both containers must be electrically bonded to each other and one must be grounded. Static discharge during pouring is a well-documented ignition source. A bonding wire between the containers and a grounding wire to earth ground is the standard setup.

How often do oily waste cans need to be emptied?

Daily, or at the end of each shift. Oily rags from drying oils like linseed oil can self-ignite through spontaneous combustion in just a few hours. Letting waste accumulate overnight in a non-rated container is asking for trouble.

What is the relationship between OSHA 1910.106 and NFPA 30?

OSHA 1910.106 is the federal legal requirement. NFPA 30 is the industry consensus standard that provides more detailed, up-to-date guidance. Many local fire codes adopt NFPA 30 directly. In practice, if you comply with NFPA 30 you will meet or exceed 1910.106 requirements.