We're sorry, but OSHAcademy doesn't work properly without JavaScript enabled. Please turn on JavaScript or install a browser that supports Javascript.

705 Hazard Communication Program
Skip to main content

Forms of Hazardous Chemicals

The standard's definition of "chemical" is much broader than that commonly used. According to the HCS, chemicals that apply may exist in one of many forms:

Hazardous mists produce vapors when spray painting.

Dusts - are finely divided particles. Example - wood dust.

Fumes - are even smaller particles usually formed when solid metal is heated and vaporized, and then condenses as tiny particles.

Fibers - are similar to dusts but are of an elongated shape. Examples - asbestos and fiberglass.

Mists and Fogs - are small liquid droplets that have been sprayed into the atmosphere forming mists or fog.

Vapors - are gases formed when liquid evaporates.

Gases - are substances that are normally airborne at room temperature. A vapor is the gaseous phase of a substance which is normally a liquid or solid at room temperature.

Solids - such as metal, treated wood, plastic.

Liquids - the most common form in the workplace.

Knowledge Check Choose the best answer for the question.

2-2. Which form of hazardous chemical is created when solid metal is heated and vaporized?