Hazardous materials are materials that are used or produced and are hazardous to people and property. They require special handling and special precautions to be taken.
Hazardous materials can cause a harmful effect on people if they come into contact with the body, by being splashed onto the skin or into the eyes, swallowed or breathed in. Some materials cause injury through fire or explosion.
Whatever their properties and their potential for injury and damage, a lot of care is needed in their handling, storage and transport.
You will find a number of hazardous materials in the workshop. They will exist in one of the following three states:
Virtually all substances can exist in all three states under the right conditions (especially temperature).
The change from solid to liquid usually occurs at a clearly defined temperature; for example, ice turns to water at 0°C. Further rises in temperature can change a liquid to a gas. In the case of water, it turns to steam at 100°C.
Most liquids will give off a vapour (that is, change from liquid to gas) at any temperature. A few solids will also give off a vapour.
Some materials, such as solvents, oils, hydrogen sulphide, acids and so on are hazardous by themselves.
Other materials are only hazardous when you do something with them.