---
title: "Hazard warnings symbols explained"
description: "Every hazard warnings symbol and what it means — 20 of them, with what each looks like and what happens if you ignore it."
url: https://atoneplace.net/symbol/hazard/
site: "At One Place"
---

# Hazard warnings symbols

20 hazard warnings symbols, each with what it looks like and what it actually requires.

| Symbol | Looks like | Means |
| --- | --- | --- |
| Exploding bomb (GHS01) | A bomb bursting with fragments flying out, black on white inside a red diamond. | Explosive, self-reactive, or an organic peroxide that can explode. |
| Flame (GHS02) | A single flame rising from a horizontal line, black on white in a red diamond. | Flammable — or a substance that heats up, ignites in air, or gives off flammable gas when wet. |
| Flame over circle (GHS03) | A flame sitting on top of a circle, black on white in a red diamond. | Oxidising — it will feed a fire, including one that has nothing else to burn with. |
| Gas cylinder (GHS04) | An upright gas cylinder in outline, black on white in a red diamond. | Gas under pressure — compressed, liquefied, refrigerated or dissolved. |
| Corrosion (GHS05) | Two test tubes pouring liquid, one onto a hand and one onto a bar of metal, both being eaten away. | Causes severe skin burns and eye damage, or corrodes metal. |
| Skull and crossbones (GHS06) | A human skull above two crossed bones, black on white in a red diamond. | Acute toxicity — fatal or toxic in small amounts by swallowing, skin contact or inhalation. |
| Exclamation mark (GHS07) | A bold exclamation mark, black on white in a red diamond. | Irritant, skin sensitiser, harmful if swallowed or inhaled, or may cause drowsiness — the lower-severity hazards. |
| Health hazard (GHS08) | A human torso in silhouette with a white starburst on the chest radiating outwards. | Serious long-term health effects — cancer, genetic damage, harm to fertility or the unborn child, organ damage, asthma from inhalation, or fatal if swallowed and it enters the airways. |
| Environment (GHS09) | A dead fish floating beside a leafless tree, black on white in a red diamond. | Hazardous to the aquatic environment — toxic to fish and other water life. |
| Orange explosive (E) | An exploding bomb, black on an orange-yellow square, sometimes with the letter E. | Explosive, under the old European system. |
| Orange oxidising (O) | A flame over a circle, black on an orange-yellow square, sometimes with the letter O. | Oxidising agent, under the old European system. |
| Orange flammable (F, F+) | A flame, black on an orange-yellow square, with the letter F or F+. | Highly flammable (F) or extremely flammable (F+), under the old European system. |
| Orange toxic (T, T+) | A skull and crossbones, black on an orange-yellow square, with the letter T or T+. | Toxic (T) or very toxic (T+), under the old European system. |
| Orange harmful or irritant (Xn, Xi) | A diagonal cross like a letter X, black on an orange-yellow square, with Xn or Xi beside it. | Harmful (Xn) or irritant (Xi), under the old European system. |
| Orange corrosive (C) | Liquid pouring from two tubes onto a hand and a bar of metal, black on an orange-yellow square, with the letter C. | Corrosive, under the old European system. |
| Orange dangerous for the environment (N) | A dead fish and a leafless tree, black on an orange-yellow square, with the letter N. | Dangerous for the environment, under the old European system. |
| NFPA 704 fire diamond | A diamond of four smaller diamonds: blue on the left, red on top, yellow on the right, white at the bottom, each holding a number from 0 to 4 or a code. | A US placard telling emergency responders how a stored chemical behaves in a fire. |
| Biohazard | Three interlocking incomplete circles arranged around a central ring, usually black on orange or on yellow. | Biological material that can cause disease — blood, cultures, clinical waste. |
| Radiation trefoil | Three black wedges radiating from a central circle, on a yellow background. | Ionising radiation — a radioactive source or a device producing radiation. |
| Laser radiation | A black starburst with a straight beam radiating from it, inside a yellow triangle with a black border. | Laser radiation — do not look into the beam. |

- [Exploding bomb (GHS01)](https://atoneplace.net/symbol/hazard-ghs-explosive/) — Explosive, self-reactive, or an organic peroxide that can explode.
- [Flame (GHS02)](https://atoneplace.net/symbol/hazard-ghs-flammable/) — Flammable — or a substance that heats up, ignites in air, or gives off flammable gas when wet.
- [Flame over circle (GHS03)](https://atoneplace.net/symbol/hazard-ghs-oxidising/) — Oxidising — it will feed a fire, including one that has nothing else to burn with.
- [Gas cylinder (GHS04)](https://atoneplace.net/symbol/hazard-ghs-gas-cylinder/) — Gas under pressure — compressed, liquefied, refrigerated or dissolved.
- [Corrosion (GHS05)](https://atoneplace.net/symbol/hazard-ghs-corrosive/) — Causes severe skin burns and eye damage, or corrodes metal.
- [Skull and crossbones (GHS06)](https://atoneplace.net/symbol/hazard-ghs-toxic/) — Acute toxicity — fatal or toxic in small amounts by swallowing, skin contact or inhalation.
- [Exclamation mark (GHS07)](https://atoneplace.net/symbol/hazard-ghs-irritant/) — Irritant, skin sensitiser, harmful if swallowed or inhaled, or may cause drowsiness — the lower-severity hazards.
- [Health hazard (GHS08)](https://atoneplace.net/symbol/hazard-ghs-health/) — Serious long-term health effects — cancer, genetic damage, harm to fertility or the unborn child, organ damage, asthma from inhalation, or fatal if swallowed and it enters the airways.
- [Environment (GHS09)](https://atoneplace.net/symbol/hazard-ghs-environment/) — Hazardous to the aquatic environment — toxic to fish and other water life.
- [Orange explosive (E)](https://atoneplace.net/symbol/hazard-eu-orange-explosive/) — Explosive, under the old European system.
- [Orange oxidising (O)](https://atoneplace.net/symbol/hazard-eu-orange-oxidising/) — Oxidising agent, under the old European system.
- [Orange flammable (F, F+)](https://atoneplace.net/symbol/hazard-eu-orange-flammable/) — Highly flammable (F) or extremely flammable (F+), under the old European system.
- [Orange toxic (T, T+)](https://atoneplace.net/symbol/hazard-eu-orange-toxic/) — Toxic (T) or very toxic (T+), under the old European system.
- [Orange harmful or irritant (Xn, Xi)](https://atoneplace.net/symbol/hazard-eu-orange-harmful/) — Harmful (Xn) or irritant (Xi), under the old European system.
- [Orange corrosive (C)](https://atoneplace.net/symbol/hazard-eu-orange-corrosive/) — Corrosive, under the old European system.
- [Orange dangerous for the environment (N)](https://atoneplace.net/symbol/hazard-eu-orange-environment/) — Dangerous for the environment, under the old European system.
- [NFPA 704 fire diamond](https://atoneplace.net/symbol/hazard-nfpa-704/) — A US placard telling emergency responders how a stored chemical behaves in a fire.
- [Biohazard](https://atoneplace.net/symbol/hazard-biohazard/) — Biological material that can cause disease — blood, cultures, clinical waste.
- [Radiation trefoil](https://atoneplace.net/symbol/hazard-radioactive/) — Ionising radiation — a radioactive source or a device producing radiation.
- [Laser radiation](https://atoneplace.net/symbol/hazard-laser/) — Laser radiation — do not look into the beam.