Hands-on Activity Demonstration: Choosing an Occupational Exposure Limit

An occupational exposure limit, or OEL, is the maximum concentration or quantity that is allowed or considered safe for hazardous agents. The purpose of an OEL is to protect workers from excessive exposures that could cause adverse health effects. The objective for this activity is for learners to be able to locate appropriate OELs to assess exposure risks of substances. Learners are given four scenarios for whcih they must select OELs and compare measured values to the OELs.

[@williamcoyle1117]

Ms. Ibe,
Can you please tell me if the data recording form used in your presentation (exposure scenarios), is part of the NIOSH guide...or...a form that you created independently.
Thank you for your clear and professional presentation.
-Bill

[@METPHASTProgram]

+William Coyle Hello, this is Pete Raynor for the METPHAST Program. Thank you for viewing our hands-on activity demo. I'm sorry to be so long in responding. We created the form as part of our instructions for this hands-on activity. You can view and download PDF files with our "Guide for Instructors" and "Instructions for Learners" for this activity at the web site nano-link.org, under the Nano Safety tab, in Module 3: Occupational Health and Safety Regulations and Guidelines. There is a free registration required for Nano-Link.

[@safetydeskltd9047]

Thank you all from METPHAST.

[@fahimdawer]

The calculation formula given by the British Safety Council is actually like this LTEL= concentration of contaminant × Exposure time/ divided by 8
your way of calculation is different so can u tell me which one is right?

[@METPHASTProgram]

Thanks for watching the video and for your question. The formula you provide looks like it is for adjusting the concentration of a contaminant when a long-term exposure is different than 8 hours. I've seen examples from the UK Health & Safety Executive where they use this formula to adjust a time-weighted average concentration taken over a work shift longer than 8 hours to a higher concentration, as though the sample were taken for only 8 hours. If this is done, the resulting elevated concentration can be compared to the LTEL to determine exposure acceptability. In the U.S., the approach is to use a similar, but inverted, formula to adjust an OEL downward to be more protective over a period longer than 8 hours: Modified OEL = 8-hour OEL x 8 hours/ work shift (in hours). The measured TWA concentration is then compared to the adjusted OEL. Either approach is acceptable if applied properly; you'll make the same decision about exposure acceptability either way.
Does this answer your question?

[@bloodymir]

@@METPHASTProgram this is one of the topics I am very interested in, is there any procedure, besides brief-scala, to adjust oels depending on unusual work shifts?
Thanks for the videos, they are very useful.