The following hazard diagram is widely used to indicate the health, fire, and reactivity of chemicals. This diagram is not only found on the label of bottles of chemicals, but on boxes, tractor trailers, railroad cars, and anywhere that chemicals might be stored. It is important to be familiar with this diagram and what the number in each section indicates in regards to the hazard presented by the chemical to which it is refering.

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Click here to find out what the meaning is of the numbers 0 - 4 that are used on the hazard diagram.

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The following terms are often used to describe the hazards of some chemicals. It is important to know these meanings, and how they differ from each other.

Carcinogen: a substance capable of causing cancer or cancerous growths in mammals.

Known labels indicate that sufficient information exists which shows a definite relationship between exposure to a substance and cancer in humans.
Probable labels indicate there is limited evidence in humans and/or sufficient evidence in experimental animals.

Mutagen: a substance capable of causing changes in the genetic material of a cell, which can be transmitted during cell division.

Highly Toxic: Agents or substances that when inhaled, absorbed or ingested in small amounts can cause death, disablement, or severe illness.

Explosive: an unstable substance capable of rapid and violent energy release.

Volatile: Easily vaporized from the liquid, or solid state.

Corrosive: a substance that causes destruction of tissue by chemical action on contact.

Irritant: a substance that on immediate, prolonged, or repeated contact with normal tissue will induce a local inflammatory reaction.

Flammable: Burns easily.