Hazard Communication and Toxic and Hazardous Substances
The worker's right to know about chemical hazards: labels, safety data sheets, pictograms and the written program, and how the body is exposed to toxic substances and how that exposure is limited and measured.
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8.1 Hazard Communication
Workers have a need and a right to know about the chemical hazards of their work. The Hazard Communication Standard, HazCom, requires every employer to give affected employees information and training on the physical hazards, such as explosive and flammable materials, and the health hazards, acute and chronic, that they may meet at work.
Key definitions
| Term | Meaning |
|---|---|
| Hazardous chemical | A chemical that is a physical or health hazard. Mixtures, fuels, solvents, paints and dusts can be hazardous. |
| Toxicity | The ability of a substance to cause harm. Almost everything is toxic at some dose. |
| Flash point | The lowest temperature at which a liquid gives off enough vapour to form a flammable mixture with air. |
| Flammable and combustible liquids | The classic division is a flash point below or at or above 100 degrees F (37.8 degrees C). Under GHS the categories are set by flash point and boiling point. |
| Container | A bag, barrel, bottle, box, can, cylinder, drum, reaction vessel, storage tank or similar holder of a hazardous chemical. |
| Exposure | A worker is subjected to a hazardous chemical as a condition of the job, including possible exposure, by any route: inhalation, ingestion, skin contact, absorption or injection. |
| Hazard warning | Words, pictures or symbols on a label that tell of the specific hazards, including target organ effects. |
| Immediate use | The chemical is controlled by and used only by the person who transfers it, during the same shift. |
| Organic peroxide | A carbon compound with two oxygen atoms joined, which can be a severe fire and explosion hazard. |
| Oxidiser | A chemical that starts or helps combustion in other materials. |
| Pyrophoric | A chemical that ignites spontaneously in air at 130 degrees F (54.4 degrees C) or below. |
| Unstable (reactive) | A chemical that vigorously polymerises, decomposes or becomes self reactive under shock, pressure or temperature. |
| Water reactive | A chemical that reacts with water to release a flammable or hazardous gas. |
Labels
A label is any written, printed or graphic material on or attached to a container of hazardous chemicals. Labels are the most immediate source of information about a chemical, and every container of hazardous chemicals must be labelled. A GHS label has six elements:
- The product identifier.
- A signal word: Danger for the more severe hazards, Warning for the less severe.
- Pictograms.
- Hazard statements.
- Precautionary statements.
- The name, address and phone number of the supplier.
A study aid, not published or endorsed by IOSH or OSHA. Laws and limits differ between countries.