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105 Hazard Communication: Basic
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105 Hazard Communication: Basic

Hazardous Substances and Chemicals

OSHA defines a substance as a chemical element and its compounds in the natural state or obtained by any production process.

Infographic of Physical & Health Hazards
Infographic of Physical & Health Hazards
Infographic of Physical & Health Hazards

This definition includes any additive necessary to preserve the stability of the product and any impurities deriving from the process used, but excludes any solvent which may be separated without affecting the stability or altering the composition of the substance.

Hazardous Substances: OSHA defines a "hazardous substance" as any chemical or material which is a physical hazard or a health hazard. They are subject to specific regulatory thresholds and reporting requirements.

  • Physical hazards include chemicals and materials that can cause physical harm by being flammable, explosive, reactive, or corrosive.
  • Health hazards include chemicals or materials that can cause acute or chronic health effects including irritation, cancer, neurotoxicity, and agents that damage the blood-forming organs, lungs, skin, eyes, or mucous membranes.

Hazardous Chemicals: OSHA defines a "hazardous chemical" as any chemical which is classified as a physical hazard, health hazard, simple asphyxiant, combustible dust, pyrophoric gas, or hazard not otherwise classified.

Below is a list of examples of hazardous chemicals.

Physical Hazards:

  • explosives
  • flammables (gases, aerosols, liquids, or solids)
  • oxidizers (liquid, solid or gas)

Health Hazards:

  • acute toxicity (any route of exposure)
  • respiratory or skin sensitization
  • specific target organ toxicity (single or repeated exposure)

Asphyxiants:

  • carbon monoxide
  • nitrogen
  • helium
  • argon

Pyrophoric Gases:

  • silane
  • arsine
  • phosphine
  • xenon

Real-Life Accidents

At 1:51 a.m. on March 26, 2018, an employee was mixing 100 pounds of pyrotechnic chemicals in a mixer. An ignition occurred as the employee was lifting the mixing blade out of the mixing bowl which caused an explosion. The employee sustained burns over 90 percent of the body and died.
At 7:54 p.m. on November 9, 2022, an employee and two coworkers were using a gasoline powered two-inch dewatering pump to remove standing water from a 54-inch culvert. When the employee did not come out of the culvert in the expected time frame, he was found unconscious and unresponsive inside the culvert. The employee was killed by asphyxiation due to high carbon monoxide concentrations inside the culvert due to the pump's exhaust fumes.

Knowledge Check Choose the best answer for the question.

1-3. Under the HCS, what is an example of a physical hazard?

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