GHS Pictograms Explained: The 9 Hazard Symbols and What They Mean
Short answer: there are nine GHS hazard pictograms — red-bordered diamonds that each signal a category of hazard — and OSHA's Hazard Communication Standard requires eight of them (all but the environmental symbol). They include the flame (flammable), corrosion (corrosive), skull and crossbones (acute toxicity), health hazard, exclamation mark (irritant), exploding bomb, flame-over-circle (oxidizer), and gas cylinder. Staff must be trained to recognize them. Here's what every symbol means and where you'll see it.
The nine GHS pictograms
- Health Hazard (silhouette with a starburst on the chest) — carcinogens, mutagens, reproductive toxicity, respiratory sensitizers, and target-organ or aspiration toxicity. The "serious long-term health effects" symbol.
- Flame — flammable liquids, solids, gases and aerosols; pyrophorics; self-heating and self-reactive substances; organic peroxides.
- Exclamation Mark — skin/eye irritation, skin sensitizers, acute toxicity (harmful), and narcotic/respiratory-irritant effects. The "less severe" health symbol.
- Gas Cylinder — gases stored under pressure (compressed, liquefied, or dissolved). Think oxygen and other cylinders.
- Corrosion — skin corrosion/burns, serious eye damage, and substances corrosive to metals. Common on bleach, drain cleaners, and strong acids/bases.
- Exploding Bomb — explosives, certain self-reactive substances, and organic peroxides.
- Flame Over Circle — oxidizers, which can intensify a fire even without air.
- Skull and Crossbones — acute toxicity that can be fatal or toxic at low doses. Far more severe than the exclamation mark.
- Environment (a dead tree and fish) — aquatic toxicity. This one is not mandatory under OSHA, though manufacturers often include it because it's part of GHS.
Where you'll see them
Pictograms appear in two places: on the product label (both the manufacturer's container and any secondary container you label) and in Section 2 of the safety data sheet. The label pictogram, signal word ("Danger" or "Warning"), and hazard statements should all line up with what the SDS says.
Why staff should know the basics
Your team doesn't need to memorize all nine, but everyone should recognize the three most common in a cleaning or care environment — Corrosion, Exclamation Mark, and Flame — and know to check the SDS when they see Skull and Crossbones or Health Hazard. That recognition is part of the HazCom training OSHA expects (see our compliance checklist).
Get the pictograms right automatically
SDSentry maps each product's hazard data to the correct GHS pictograms and prints them on ready-to-use secondary-container labels — so a diluted-bleach spray bottle shows the right corrosion symbol without anyone guessing. The same hazard data powers the per-product training guides your staff sign off on.
Frequently asked questions
How many GHS pictograms are there?
There are nine in total. OSHA's Hazard Communication Standard requires eight of them; the environmental pictogram is not mandated by OSHA but is widely used.
What do the GHS pictograms mean?
Each red-bordered diamond signals a hazard class, for example flame (flammable), corrosion (corrosive), skull and crossbones (acute toxicity), health hazard (carcinogen or respiratory hazard), exclamation mark (irritant), exploding bomb, flame over circle (oxidizer), gas cylinder, and environment.
Do employees need to know the pictograms?
Yes. HazCom training must cover how to read labels, including what the pictograms mean, so staff can recognize a product’s hazards at a glance.