Will Permissible Exposure Limits Change?

Hazardous Chemicals

Last month, OSHA issued a Request for Information in order to begin a national dialogue about permissible exposure limits (PELs) for hazardous chemicals in the workplace. This request asks stakeholders in industries that manufacture and use potentially hazardous chemicals to give their input about how OSHA could update PELs for known hazardous chemicals in a useful and manageable way.

Currently, OSHA only has exposure limits for fewer than 500 chemicals used in the workplace, even though thousands are used by employees on a daily basis. PELs for these chemicals were established more than 40 years ago, and since then, very few have been updated to reflect current science and health research because each chemical must go through OSHA’s standard rule-making process (which is not quick). What does this mean for workers? It means many of them are being exposed to chemicals on a regular basis that do not have enforceable exposure limits or whose limits are outdated.

“Past efforts to update our PELs have largely been unsuccessful. Since 1971, OSHA has successfully established or updated PELs for only about 30 chemicals. We have issued only one new exposure limit since the year 2000. As a result, many workers are currently being exposed to levels of chemicals that are legal, but not safe,” David Michaels, Assistant Secretary of Labor for Occupational Safety and Health, said in a statement.

Michaels also points out that these chemicals are often silent killers, not the obvious hazards you see every day in the workplace like fall hazards and dangerous machinery.

According to OSHA’s toolkit for transitioning to safer chemicals, workers suffer more than 190,000 illnesses and 50,000 deaths each year that are related to chemical exposures. These exposures can impact the lungs, kidneys, stomach, heart, skin, brain and reproductive organs, and in some cases have been linked to cancers.

To begin tackling this serious safety issue, OSHA is asking for comments about strategies for updating PELs, as well as the best approaches for managing chemical hazards in the workplace. They seek information about approaches such as control banding, task-based strategies and informed substitution.

Since current OSHA regulations may not provide enough protection for workers, knowing what to do at your business may seem daunting. Understanding the hazards present and taking steps to lessen them is the best way to take control of of the situation in your workplace.

Chemical Hazards

Permissible Exposure Limits – Definitions

A permissible exposure limit is defined as a regulatory limit of the amount/concentration of a substance in the air. PELs are set to protect workers from the health effects of exposures to hazardous substances.

To determine whether a substance has reached the PEL, the presence of chemicals is measured over an eight-hour period and that average is used. (This is called the time-weighted average (TWA)).

Employers must comply with these limits, but since many of the PELs are not stringent enough to protect workers, extra precautions may be necessary to prevent injuries and illnesses. 

PEL Resources

OSHA notes that several other agencies have resources that can help guide businesses through the confusion surrounding exposure limits.

  • Cal-OSHA, California’s state-run OSHA, has the most extensive list of PELs of any state-run program. Their list can provide guidance about many chemicals.
  • The National Institute for Occupational Safety and Health (NIOSH) has developed recommended exposure limits (RELs) based on medical, biological, chemical, engineering and trade information.
  • OSHA’s Annotated PEL Tables provide a side-by-side comparison of OSHA’s PELs and the recommended limits of other agencies, which may be helpful for employers, too. 


What Employers Can Do About Hazardous Chemicals

Besides educating yourself about exposure limits and determining what chemical hazards impact your workplace, you can take some concrete steps to reduce these hazards. 


Many industries must use specific chemicals in their manufacturing processes, and in some cases, substituting a less hazardous chemical for a hazardous one can be difficult. In other cases, though, it’s possible to select a less dangerous chemical for your workplace.

If your facility uses harsh cleaning chemicals, for example, you might be able to find a safer alternative that will still get the job done.

OSHA has put together an online toolkit to help employers select less hazardous chemicals. This process begins with an “alternatives assessment” and involves “identifying, comparing, and selecting safer alternatives for hazardous chemicals on the basis of their hazards, performance, and economic viability.” In some cases, safer chemicals perform just as well as the original chemicals and can even help the company save money.

Change Processes 

Maybe you can’t swap the chemicals you currently use for safer ones, but it might be possible to change your work processes to reduce chemical exposures.

Perhaps you could still use the chemical, but reduce the amount of time employees handle it. OSHA gives an example of this from DuPont Corporation. The company implemented a new technology for producing a toxic chemical, which reduced worker handling of the substance. 

Provide PPE & Emergency Supplies

respiratory protection
Respirators can protect employees from some types of chemical hazards.

When you can’t change your processes or the chemicals involved in them, make sure proper protective measures are taken in your facility. If you know a chemical could be hazardous to the lungs, provide respirators. If skin sensitivity could be an issue, provide gloves.

NIOSH’s Pocket Guide to Chemical Hazards provides information about what parts of the body need to be protected from various chemicals, so see if the chemicals you use are listed in it.

Whenever any chemical hazards are present in the workplace, make sure you also have proper emergency equipment such as emergency eyewash stations, showers, fire extinguishers and first aid kits. Provide training in how to use these things so employees know what to do if an accident happens.

Finally, be sure to label all of your site’s hazardous chemicals appropriately using the new Globally Harmonized System requirements so everyone can easily find out important information about hazardous chemicals such as first aid and PPE requirements.

Share Your Input on Chemical PELs

Do you have input about managing hazardous chemicals in the workplace? You can submit comments to OSHA at regulations.gov through April 8, 2015. 

To learn more about hazardous chemicals and the new GHS requirements, take a look at the SlideShare below:

GHS – It Is Ready, Are You? from Creative Safety Supply

Additional Resources