What Is an OSHA-Approved Safety Can or Fuel Container?

The following article was published by CONN-OSHA. It is reprinted here with permission.

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Safety cans and fuel containers are commonly used across general industry and construction worksites.

However, confusion often arises regarding what constitutes an “approved” container, particularly under the Occupational Safety and Health Administration regulations.

This article focuses on OSHA’s General Industry Standard, 29 CFR 1910.106, and the Construction Standard, 29 CFR 1926.155.

It clarifies definitions, requirements for container approval, flammable liquid classifications, and the proper use and handling of these containers in the workplace.

Background

The early 20th century saw a surge in industrial accidents that galvanized public and governmental interest in workplace safety.

Prior to the formalization of workplace safety standards, flammable liquids were commonly stored in open or poorly sealed containers, resulting in frequent fires and explosions.

Manufacturers began to develop specialized containers with built-in safety mechanisms, including spring-loaded lids, flame arresters, and pressure-relief valves.

These innovations marked the beginning of what would become standardized safety cans.

OSHA Definitions

OSHA defines several key terms in 29 CFR 1910.106:

• Container: “Any can, barrel, or drum” used to hold flammable or combustible liquids 29 CFR 1910.106(a)(29)
•  Approved: “Listed or approved by a nationally recognized testing laboratory” (NRTL) 29 CFR 1910.106(a)(35)
• Safety Can: “An approved container, of not more than 5 gallons capacity, having a spring-closing lid and spout cover and designed so it will safely relieve internal pressure when subjected to fire exposure” 29 CFR 1910.106(a)(34)

The Construction Standard (29 CFR 1926.155(l)) adds that a safety can must also include a flash-arresting or flame-arresting screen.

OSHA Flammable Liquid Classification

OSHA classifies flammable liquids ((29 CFR 1910.106(a)(19) and 1926.155)) based on flash point and boiling point:

Nationally Recognized Testing Laboratories. NRTLs, as defined by OSHA in 29 CFR 1910.7, are independent organizations authorized to perform safety testing and certification.

Two laboratories that test and certify safety cans are Underwriters Laboratories and FM Approvals.

Flame-Arresting Screen Interpretation Letter. A key difference between the General Industry and Construction Standard safety can definitions is the flame-arresting screen requirement.

While UL does not or did not mandate flame arrestors for certification, FM requires them, leading to distinctions between containers compliant under different NRTLs.

In an Enforcement Directive, OSHA clarified that the use of UL-approved safety cans without flame arrestors is considered a de minimis violation or an infraction without a direct relationship to safety or health and thus not subject to citation.

However, removing a screen from a can designed with one by the manufacturer may result in a citation.

Design and Functionality of Safety Cans

Safety cans are typically constructed of steel or high-density polyethylene and feature a range of safety mechanisms.

Flame arresters prevent external ignition sources from igniting vapor inside the can, while self-closing lids reduce the likelihood of spillage and vapor escape.

Pressure relief features ensure that the can does not rupture under high internal pressure.

Two primary types of safety cans exist: Type I and Type II.

Type I cans have a single opening for both pouring and filling, whereas Type II cans feature separate openings and include metal flexible dispensing spouts.

These variations allow for more precise control in specific applications, from laboratories to construction sites.

OSHA Color Coding and Identification

Safety cans for flammable liquids with a flash point at or below 80°F must be painted red, with either a yellow band or the name of the contents stenciled in yellow (29 CFR 1910.144).

Industry best practice color coding for containers:

Container Size Limits. Under 29 CFR 1910.106(e)(2)(ii):

• Category 1 liquids: Maximum size = 2 gallons
• Category 2–4 liquids: Maximum size = 5 gallons

These limits apply to safety cans used in labs, maintenance shops, and other work environments.

Bonding and Grounding Requirements. For flammable liquids with flash points below 100°F, OSHA requires bonding and grounding during dispensing to prevent static discharge 29 CFR 1910.106(e)(6)(ii):

• Bonding connects the dispensing container and receiving container
• Grounding ensures both containers are at the same electrical potential
• Metal safety cans are naturally conductive
• High-Density Polyethylene (HDPE) safety cans can include internal conductive paths for grounding

Hazards of Consumer Fuel Containers. Improper use of consumer containers in the workplace poses serious hazards that include:

• Vapor release can cause flashback ignition
• Pressure buildup may lead to rupture or explosion
• Flame jetting or a sudden flame projection during pouring, especially near ignition sources

Only NRTL-approved safety cans should be used for handling flammable liquids in the workplace.

Conclusion

Safety cans are indispensable tools in the safe storage and handling of flammable liquids.

Their development has been closely tied to the historical recognition of industrial hazards and the evolution of regulatory requirements.

The use of NRTL-approved safety cans and proper work practices that include labeling, bonding and grounding, and the adherence to capacity limits play a vital role in reducing the risk of fire and injury in the workplace.

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About the author: Benjamin Stephens is an occupational hygienist with CONN-OSHA.