The GHS Gas Cylinder Pictogram: What It Means

Short answer: the gas cylinder pictogram warns of gases or chemicals under pressure that may explode if heated, or refrigerated gases that can cause cryogenic burns. It is one of the eight pictograms OSHA requires on chemical labels.

What the gas cylinder covers

OSHA's Hazard Communication Standard pictogram QuickCard (OSHA 3491, 2024 revision) lists:

• Gases under pressure
• Chemicals under pressure

Hazard statements and signal words

From Appendix C to 29 CFR 1910.1200, section C.4:

Gases under pressure always carry Warning. A cylinder can still show Danger because of another hazard of the gas inside — a flammable gas also takes the flame, and an oxidizing gas takes the flame over circle. Aerosol cans are a separate class: flammable aerosols use the flame, and non-flammable aerosols (category 3, “Pressurized container: may burst if heated”) carry no pictogram.

What it looks like

Appendix C to 29 CFR 1910.1200 defines every pictogram the same way: a square set at a point with a black hazard symbol on a white background and a red frame wide enough to be clearly visible (C.2.3.1), which is why pictograms look like red diamonds. A red frame with no symbol inside is not a pictogram and is not permitted on a label, and each pictogram may appear only once on a label even when several hazards call for it (C.2.3.4).

Frequently asked questions

What does the gas cylinder pictogram mean?

It warns of gases or chemicals under pressure. Compressed, liquefied and dissolved gases may explode if heated, and refrigerated liquefied gases may cause cryogenic burns or injury.

What signal word goes with the gas cylinder pictogram?

Gases under pressure carry Warning. Chemicals under pressure carry Danger in category 1 and Warning in categories 2 and 3. A label shows Danger if any other hazard of the product calls for it.

Do aerosol cans show the gas cylinder pictogram?

No. Aerosols are their own hazard class: flammable aerosols use the flame pictogram, and category 3 aerosols carry the statement Pressurized container: may burst if heated with no pictogram.

This guide summarises the cited rules for general information and is not legal advice.

Related guides

• The Health Hazard Pictogram
• The Corrosion Pictogram
• The Flame Pictogram
• The Skull and Crossbones Pictogram
• The Exploding Bomb Pictogram
• The Environment Pictogram
• Free GHS Label Maker (print secondary container labels)
• The GHS Flame Over Circle Pictogram
• GHS Pictograms Explained: The 9 Hazard Symbols
• The GHS Exclamation Mark Pictogram
• GHS Signal Words: Danger vs. Warning
• GHS Label Requirements
• Secondary Container Labeling Under GHS
• The 16 Sections of an SDS Explained
• Propane SDS: Hazards, Cylinder Storage and Where to Get the Current Sheet
• Acetylene SDS: Hazards, Cylinder Rules and Where to Get the Current Sheet
• Nitrogen SDS: Compressed Gas, Asphyxiation Hazard and Where to Get It
• Argon SDS: Welding Gas Hazards, Cylinder Storage and Where to Get It
• Carbon Dioxide (CO2) SDS: Cylinder Hazards and Where to Get the Sheet