You see them on drums, bottles, and shipping labels: a red diamond with a black symbol inside. If you can't tell a flame from a flame over a circle at a glance, you risk storing, mixing, or handling a chemical the wrong way. Learning to read hazard symbols is one of the fastest ways to cut chemical risk in your workplace.
The Globally Harmonized System (GHS) uses nine pictograms, and each one points to a specific type of danger. They cover physical hazards like fire, explosions, and compressed gas, health hazards like toxicity, corrosion, and carcinogens, and environmental harm. OSHA's Hazard Communication Standard requires them on labels for most hazardous chemicals.
Below, you'll find each pictogram, what it means, and the products it typically appears on. We also cover what you should do when you see it. At Safety Decals, we make custom GHS labels and safety decals for facilities across the country, so we've included notes on durable, compliant labeling to help you keep every container clearly marked.
Why GHS hazard symbols matter in the workplace
A shared language that works in seconds
Chemical incidents often start with a misunderstanding, not a lack of equipment. Hazard symbols replace guesswork with a standard visual code that a new hire, a forklift driver, and a visiting contractor can all read in two seconds. Because the GHS is used in many countries, the same pictogram means the same thing on a drum from overseas as on a bottle from a local supplier.
A pictogram tells you what kind of danger you're facing before you read a single word.
Language barriers matter too. A warehouse crew may speak several languages, but a skull and crossbones needs no translation. That makes pictograms your first line of defense when text is smudged, small, or skipped.
What the rules require
OSHA's Hazard Communication Standard (29 CFR 1910.1200) requires pictograms on shipped container labels for hazardous chemicals. It also expects employers to keep workplace containers labeled and workers trained to understand them. Symbols you can't read or find don't meet that goal.
Good labeling prevents the mistakes that cause real injuries:
- Storing oxidizers next to flammables
- Choosing the wrong gloves, goggles, or respirator
- Responding to a spill with the wrong cleanup method
- Pouring chemicals into unmarked secondary containers
Faded, peeling, or missing labels undo all of this. Check your containers, shelves, and tanks regularly, and replace any label that has lost its color, adhesion, or legibility before it becomes a gap in your safety program.
What each of the 9 GHS pictograms means
Each pictogram is a black symbol on a white background inside a red diamond. It names the type of hazard, not how severe it is. Learn these nine and you can sort any chemical by risk at a glance.
The pictogram tells you what the hazard is; the signal word tells you how serious it is.
The nine pictograms at a glance
Use this table for training sheets and storage areas. Physical hazards come first, then health and environmental hazards.
| Pictogram | Signals | Example |
|---|---|---|
| Exploding bomb | Explosives, organic peroxides | Fireworks |
| Flame | Flammables, pyrophorics | Acetone |
| Flame over circle | Oxidizers | Hydrogen peroxide |
| Gas cylinder | Gases under pressure | Propane |
| Corrosion | Skin burns, eye damage | Drain cleaner |
| Skull and crossbones | Acutely toxic | Cyanide |
| Exclamation mark | Irritants, sensitizers | Degreasers |
| Health hazard | Carcinogens, organ damage | Benzene |
| Environment | Aquatic toxicity | Pesticides |
Note that OSHA doesn't mandate the environment pictogram, yet suppliers often print it, so treat it as a real warning for disposal and spills.
How to read a GHS label beyond the pictogram
Hazard symbols are only one part of a GHS label. OSHA requires six elements on every shipped container, and reading them together gives you the full risk picture.
The six required elements
Start with the product name and work down. Each element answers a different question, so don't stop at the red diamond. Use this order as a quick check:
- Product identifier: matches the name on the Safety Data Sheet (SDS)
- Signal word: "Danger" for severe hazards, "Warning" for lesser ones
- Pictograms: the type of hazard
- Hazard statements: plain sentences like "Causes severe skin burns"
- Precautionary statements: how to store, handle, and respond
- Supplier details: name, address, and phone number
When the label isn't enough
Labels are short by design. For exposure limits, first aid, and spill procedures, open the SDS, which has 16 sections. Keep it within reach of workers, not in a locked office.
Precautionary statements deserve a close read before you begin any task. They tell you which gloves, ventilation, and storage rules apply.
The symbol warns you; the words on the label tell you what to do about it.
How to apply hazard symbols safely at work
Label, store, and separate
Start with an inventory. Walk your site and list every chemical, then match each container to its SDS and pictograms. Spray bottles and day tanks count too, so copy the product identifier and hazard symbols onto every secondary container.
Group chemicals by hazard, not by convenience:
- Flame: keep away from heat and ignition sources
- Flame over circle: separate from flammables
- Corrosion: store low, with spill containment
- Gas cylinder: secure upright and capped
Train and maintain
Training works best with real containers. Show workers the pictograms on actual products, then ask what each one means and what to do about it. Repeat this yearly and whenever a new chemical arrives.
Finally, inspect labels monthly. Replace anything faded, scuffed, or peeling with chemical-resistant labels so your hazard symbols stay readable in wet, hot, or dirty areas.
Every container you handle should carry the same hazard symbols you would find on the original label.
Common mistakes and examples of pictograms in practice
Mistakes that cause trouble
Most errors with hazard symbols are predictable. The biggest is treating the exclamation mark as "minor." Irritants and sensitizers can still trigger repeated, serious reactions. Another is confusing corrosion with the health hazard symbol. One burns on contact, the other harms organs over time.
- Assuming a missing pictogram means a product is safe
- Reading the symbol but skipping the signal word
- Mixing up NFPA diamonds with GHS pictograms
Never treat the exclamation mark as the "mild" pictogram.
Pictograms in practice
Picture a bottle of bleach-based cleaner. Corrosion plus exclamation mark tells you it burns skin and irritates airways, so you wear splash goggles and gloves and keep it away from ammonia products. Now picture paint thinner. Flame plus health hazard means fire risk and organ damage from vapors, so you ventilate the area and remove ignition sources before opening the can.
Putting hazard symbols to work
Nine pictograms carry one simple idea: a symbol tells you the type of hazard before you read a single word. Pair each one with its signal word and precautionary statements, and you can handle, store, and separate chemicals with confidence and consistency.
Knowing hazard symbols only helps if workers can see them. Labels that fade, peel, or go missing leave gaps in your program, so inspect containers often and replace worn ones right away. Keep the SDS within reach, and train people on real containers at least once a year.
Safety Decals makes durable, customizable GHS labels and safety decals from ORAFOL materials that hold up in wet, hot, and dirty areas. When you're ready to mark every container clearly and correctly, order custom hazard labels and safety decals from Safety Decals.
