To encourage employers to adopt more protective measures for employee exposure to airborne substances, OSHA has launched a website tool ( that provides a side-by-side comparison of OSHA Permissible Exposure Limits (PELs) for general industry with exposure recommendations from three other sources: the California Division of Occupational Safety and Health, National Institute for Occupational Safety and Health (NIOSH) and American Conference of Governmental Industrial Hygienists (ACGIH). The annotated PELs are merely recommendations.

Although the agency has legally enforceable PELs for many substances, they have not been updated in more than 40 years. OSHA attempted to update PELs on nearly 400 chemical substances more than two decades ago, but the effort was struck down in court. The agency does not believe the current PELs adequately protect workers. OSHA hopes its Annotated Permissible Exposure Limits tables will enable employers to adopt newer, more protective workplace exposure limits voluntarily.

“There is no question that many of OSHA’s chemical standards are not adequately protective,” OSHA Assistant Secretary Dr. David Michaels admits. “I advise employers, who want to ensure that their workplaces are safe, to  utilize the occupational exposure limits on these annotated tables, since simply complying with OSHA’s antiquated PELs will not guarantee that workers will be safe.”

Many of the NIOSH Recommended Exposure Limits (RELs) and ACGIH Threshold Limit Values (TLVs) are stricter than what OSHA requires, they were adopted without notice- and-comment rulemaking or evaluation of technical or economic feasibility.

The agency also released a second online resource to assist operators seeking to replace hazardous chemicals with less hazardous materials. The toolkit ( walks employers and workers through information, methods, tools and guidance to eliminate hazardous chemicals or to make informed decisions enabling selection of a safer chemical, material, product or process.