GHS Pictograms: 9 Hazard Symbols, Meanings & Printable Poster

The 9 hazard symbols at a glance

• GHS01 Exploding bomb: explosives, and self-reactive substances and organic peroxides that can explode.
• GHS02 Flame: flammable gases, aerosols, liquids and solids, pyrophoric and self-heating substances, and those that release flammable gas with water.
• GHS03 Flame over circle: oxidizing gases, liquids and solids.
• GHS04 Gas cylinder: gases under pressure, including compressed, liquefied, dissolved and refrigerated gases.
• GHS05 Corrosion: skin corrosion, serious eye damage and corrosive to metals.
• GHS06 Skull and crossbones: acute toxicity, categories 1 to 3.
• GHS07 Exclamation mark: irritants, skin sensitizers, acute toxicity category 4 and narcotic or respiratory irritation effects.
• GHS08 Health hazard: carcinogens, mutagens, reproductive toxicants, respiratory sensitizers, target organ toxicity and aspiration hazards.
• GHS09 Environment: hazardous to the aquatic environment.

Signal words: Danger and Warning

Pictograms are paired with a signal word. Danger is used for the more severe hazards and Warning for the less severe ones. The signal word belongs to the hazard category, not to the pictogram itself, so the same pictogram can appear with either word. For example, the flame goes with Danger for a category 1 or 2 flammable liquid and with Warning for category 3. The gas cylinder is always Warning and the skull and crossbones is always Danger. OSHA also sets precedence rules: when Danger applies, Warning does not appear, the skull and crossbones replaces the exclamation mark for acute toxicity, the corrosion pictogram replaces the exclamation mark for skin or eye irritation, and when the health hazard pictogram is used for respiratory sensitization, the exclamation mark is not used for skin sensitization or skin or eye irritation.

Where to find pictograms on labels and SDS

On a container, pictograms sit next to the product identifier, signal word, hazard statements, precautionary statements and the supplier name, address and telephone number. Each pictogram appears only once on a label, even if several hazards call for it (OSHA Quick Card). On a safety data sheet, look at Section 2, Hazard identification, where the classification, signal word, hazard statements and symbols are listed. OSHA allows the symbols in an SDS to be shown as black and white graphics or simply by the name of the symbol. Section 14 covers transport information. OSHA does not enforce sections 12 to 15 (other agencies regulate those topics), although an SDS still includes them.

OSHA, the environment pictogram and transport labels

In the United States, the OSHA Hazard Communication Standard (HazCom 2012, updated in 2024) does not require the environment pictogram. OSHA lists it as non-mandatory on its quick card, and OSHA does not enforce SDS Section 12, ecological information (other agencies regulate that topic), although an SDS still includes it. Other systems, including EU CLP, do use it. Transport labels are a separate system. DOT and UN transport labels are colored diamonds placed on shipping packages and are not GHS pictograms, although they share some symbols. On a shipped container that already carries a DOT pictogram for a hazard, OSHA does not require the GHS pictogram for the same hazard (29 CFR 1910.1200(f)(5)(iii)).

How to use the poster and signs in a lab

Post the pictogram poster near chemical storage, the prep room and the fume hood so students can match a symbol to its meaning. Use it as a reference during safety training, and combine it with a few real container labels so students practice reading signal words and statements. The poster does not replace the label on a container or the safety data sheet. The lab safety sign sheet adds the signs students see around a lab: eye protection, gloves, biohazard, radiation, laser, eyewash, emergency shower, first aid and fire extinguisher. These are simplified illustrations, so for official signage choose signs that match your institution or local regulations.