OSHA's hazard communication standard (HCS) describes a hazardous chemical as any chemical that can be a physical hazard or a health hazard. Based on statistically significant or scientifically valid evidence, HCS defines most hazards as the following:
Physical hazards
A physical hazard is a chemical that is likely to burn or can cause a fire. It can release high pressure that can cause injury to the body or cause an explosion. It can react spontaneously or when exposed to water. Three types of physical hazards are:
- Fire hazards. These can be a combustible liquid, flammable liquid, flammable aerosol, flammable gas, or flammable solid. It can be an oxidizer. It can be a pyrophoric (a substance that catches fire when exposed to air).
- Reactive hazards. These can be an organic peroxide, an unstable (reactive), or a water-reactive.
- Explosion hazards. This is compressed gas or an explosive.
Health hazards
Health hazards are health effects that can result from a chemical exposure. These types of hazardous chemical exposures usually occur in a work environment. The information is based on scientific experiments on lab animals, reliable human data, cell and tissue studies, or data on chemical toxicities. Two types of health hazards are:
- Systemic effects. These can be caused by a carcinogen, toxic agent, highly toxic agent, corrosive, irritant, or sensitizer.
- Target organ effects. These can be caused by a hepatotoxin, nephrotoxin, neurotoxin, or blood/hematopoietic toxin. They can be caused by a respiratory toxin or reproductive toxin. They can be caused by a cutaneous (skin) hazard or an eye hazard.
Other hazards can cause:
- Cardiovascular, endocrine system, sensory organ, and gastrointestinal toxicity.
- Immunotoxicity.
- Skeletal/muscular and connective tissue effects.