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Recommended exposure limit
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<h2 id="understanding-and-applying-niosh-recommended-exposure-limits">Understanding and applying NIOSH recommended exposure limits</h2> <p><a href="/facts/National_Institute_for_Occupational_Safety_and_Health/5WjdDNMN">National Institute for Occupational Safety and Health</a> (NIOSH) RELs are designed to protect the health and well-being of workers by recommending safe exposure levels. To really use these guidelines well, safety professionals need to understand the recommended exposure levels, how to measure them, and ways to make sure workers aren't exposed to harmful stuff. It's not just about knowing the numbers; it's also about checking regularly and making changes if needed to keep everyone safe. </p><p>RELs are written as <a href="/facts/Permissible_exposure_limit/IrQeETWy">time-weighted average</a> (TWA) exposures. This TWA is calculated for a standard workday of up to 10 hours, over a 40-hour workweek. This is slightly different to <a href="/facts/Permissible_exposure_limit/IrQeETWy">permissible exposure limit</a> (PELs), which are calculated for 8 hours over a 40-hour workweek instead.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> NIOSH recognizes that certain scenarios demand more immediate attention and has therefore introduced additional measures. Sometimes it's not always about the whole day and a worker might be around a lot of the stuff in a short burst. So, they set a <a href="/facts/Short-term_exposure_limit/RHSQtE4z">short-term exposure limit</a> (STEL), meaning the concentration of a substance that should never be exceeded within a specified 15-minute period. There is also a ceiling limit (C). This is a substance no one should be exposed to, even for a moment. These guidelines aim to strike a balance; it is to keep workers safe from harm without going overboard and making things inefficient in the workplace. The RELs, unlike permissible exposure limits or PELs set by <a href="/facts/Occupational_Safety_and_Health_Administration/dCGbW5Ax">OSHA</a>, are merely guidelines -- they are not legally enforceable. An employer cannot be held liable, but they can try to implement these in the workplace. These guidelines are crucial for workplace safety. RELs undergo more frequent revisions and tend to be more stringent compared to PELs established by OSHA.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> The strictness inherent in RELs align with the latest scientific understanding and advancements in occupational health.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> This prioritizes knowledge in worker safety. </p> <h2 id="external-links">External links</h2> <ul><li><a href="https://www.cdc.gov/niosh/npg/">NIOSH Pocket Guide to Chemical Hazards</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Centers for Disease Control and Prevention (1988). "NIOSH Recommendations for Occupational Safety and Health Standards 1988". MMWR. 37: 1–29. <a href="https://wonder.cdc.gov/wonder/prevguid/p0000156/p0000156.asp" target="_blank">https://wonder.cdc.gov/wonder/prevguid/p0000156/p0000156.asp</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>"Recommended Exposure Limit - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2023-11-14. <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/recommended-exposure-limit#:~:text=Recommended%20exposure%20limit%20(REL)%20is,RELs%20are%20not%20regulations" target="_blank">https://www.sciencedirect.com/topics/medicine-and-dentistry/recommended-exposure-limit#:~:text=Recommended%20exposure%20limit%20(REL)%20is,RELs%20are%20not%20regulations</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>"NIOSH Pocket Guide to Chemical Hazards". NIOSH website. Retrieved November 25, 2019. This article incorporates text from this source, which is in the public domain. <a href="https://www.cdc.gov/niosh/npg/pgintrod.html" target="_blank">https://www.cdc.gov/niosh/npg/pgintrod.html</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> </ol>