A pictogram is a small picture on a label that shows the type of hazard at a glance. Most WHMIS pictograms are a black symbol on a white background inside a red border shaped like a square standing on one of its corners (a diamond).
This course has no pictures, so each pictogram is described in words. Your employer's training and the labels at your workplace will show you what they look like.
The pictograms and what they mean
Flame — a black flame. Means a fire hazard. Used for flammable gases, aerosols, flammable liquids and solids, pyrophoric liquids and solids, self-heating substances, substances that give off flammable gas in contact with water, some self-reactive substances and organic peroxides, and chemicals under pressure that are flammable.
Flame over circle — a flame sitting on top of a circle (the letter "O"). Means an oxidizer. Oxidizers do not always burn themselves, but they give off oxygen or help other materials burn, so they can make a fire start more easily or burn more strongly. Used for oxidizing gases, liquids and solids.
Gas cylinder — a gas cylinder (a tall bottle) lying on its side. Means gas under pressure. The container could explode if heated, and some refrigerated gases can cause cold burns. Used for gases under pressure and for chemicals under pressure.
Corrosion — liquid dripping from two test tubes onto a hand and onto a piece of metal, which are being eaten away. Means the product can burn and destroy skin, cause serious eye damage, or corrode metals.
Exploding bomb — a bomb bursting outward. Means an explosion or reactivity hazard. Used for the most dangerous self-reactive substances and organic peroxides (Types A and B).
Skull and crossbones — a skull with two crossed bones under it. Means acute toxicity in the most severe categories: the product can cause death or serious poisoning after a single or short exposure, even in small amounts.
Health hazard — the outline of a person's upper body with a star-like burst on the chest. Means a serious long-term or other serious health hazard: it can cause cancer, damage genes, harm fertility or an unborn child, cause allergy or asthma symptoms when breathed in, damage organs, or damage the lungs if swallowed (aspiration hazard).
Exclamation mark — a large exclamation mark (!). Means a less severe health hazard: it may irritate skin or eyes, cause a skin allergy, be harmful (less toxic than skull-and-crossbones products) or cause drowsiness, dizziness or irritation of the airways.
Biohazardous infectious materials — the biohazard symbol: three curved "C" shapes joined around a small circle. This is the one WHMIS pictogram that is not in a red diamond: it sits inside a black circle. Means the material contains organisms or toxins that can cause disease in people or animals. You may see it in laboratories, health care and some waste handling.
Environment — a dead tree and a dead fish beside water. Means a hazard to aquatic life and the environment. This pictogram comes from GHS. It is not required in WHMIS, because WHMIS did not adopt the environmental hazard classes, but you may still see it on some labels.
Points to remember
- Two products with the same pictogram can have very different levels of danger. Always read the signal word and hazard statements too.
- One product can have several pictograms. For example, a solvent might show both the flame and the health hazard pictograms.
- Some hazard categories have no pictogram. For example, the least severe category of flammable liquids has a signal word and hazard statement but no pictogram. "No pictogram" does not always mean "no hazard".
- The old WHMIS 1988 symbols were inside a circle and are no longer used (except the biohazard symbol, which WHMIS 2015 kept in its circle). If you find a product with only an old WHMIS 1988 label, tell your supervisor.
Quick memory tips
- Flame = it burns. Flame over circle = it makes other things burn better.
- Skull and crossbones = small amounts can kill. Exclamation mark = harmful, irritating, less severe.
- Health hazard (person with a burst on the chest) = serious harm that may appear later, like cancer or lung damage.
- Corrosion = destroys skin, eyes or metal.