Eyes, lungs, skin and certain chemicals don’t mix. But not all protective equipment (PPE) protects against chemical hazards.

To avoid potentially serious injury from inhaling dangerous fumes, vapors, dusts or fibers, getting chemical mist or fumes in the eyes or getting chemicals on the skin (and possibly into the bloodstream), choosing the right PPE based on a hazard assessment is essential.

According to the U.S. Department of Health & Human Services, there are four levels of PPE based on the severity of the chemical threat: A, B, C and D.

Level A

This level of protection is reserved for workers at the greatest risk of exposure to the most harmful chemicals through inhalation or skin contact, as well as those working in confined, poorly ventilated spaces. It calls for the use of:

• Positive-pressure, self-contained breathing apparatus (SCBA) or a positive-pressure respirator with an escape SCBA
• Fully encapsulating chemical protective suit
• Inner and outer chemical resistant gloves
• Chemical-resistant, steel-toe boots

Level B

Level B is similar to Level A but it provides for situations in which the threat of injury to the eyes or skin is less severe. In Level B scenarios, all Level A PPE is required except the fully encapsulating suit. Instead, workers can wear chemical-resistant clothing such as:

• Overalls and long-sleeved jacket
• Coveralls
• Hooded two-piece chemical splash suit
• Disposable, chemical-resistant coveralls

Level C

In work environments where the threat of skin exposure is minimal and periodic monitoring verifies that airborne chemical contaminants are under control, Level B protection applies, but instead of an SCBA, workers can wear a full-face or half-mask air-purifying respirator.    

Level D

D-level PPE is appropriate against “nuisance contamination” only. It’s worn when the chance of contact with chemicals is negligible and no skin or respiratory hazards exist. Necessary PPE in these conditions include a standard work uniform of coveralls and chemical-resistant work boots. Gloves, hardhat, face shield, safety glasses and escape mask may also be appropriate depending on the hazard assessment.

Even using all the right PPE is not a guarantee against injury from chemical exposure. The best approach to safety is controlling or eliminating workers’ exposure to hazards. Training is also key. Employers should train workers not only in proper PPE use but also in correct handling procedures, good hygiene practices and exposure procedures.

For more information on chemical hazards and chemical hazard communication and training, visit the Occupational Safety and Health Administration's Chemical Hazards and Toxic Substances web page. Download the National Institute for Occupational Safety and Health’s Pocket Guide to Chemical Hazards here.