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From: Oetzi**At_Symbol_Here**OPTIMUM.NET
Subject: Re: [DCHAS-L] How would you answer this student question?
Date: Aug 20, 2021 18:14 UTC
Reply-To:
ACS Division of Chemical Health and Safety
In-Reply-To: Re: [DCHAS-L] How would you answer this student question?
On August 20, 2021 at 11:39 AM Jeffrey Lewin <jclewin**At_Symbol_Here**MTU.EDU> wrote:
"For chemistry labs: I saw someone saying "if there is a splash", but if there is a splash that is a lab accident! If the mask was not there the splash would have been to the face! I also saw: "volatile compounds" but if someone is breathing in things with a mask they would be breathing it in in "normal days" (aka non-COVID-19 times) as well! So in that case they should be working in the fume hood. So in the case of a chemistry lab, in my opinion it doesn't really matter."
If a lab procedures is following appropriate Engineering and Administrative controls there should be little chance of contaminating face coverings. However, it is often the human element that is hard to control. One challenge, and I'm guilty of this, is adjusting or touching your mask with potentially contaminated fingers.
Then again, even when you know you are working with infectious materials it is common for researchers to unconsciously touch their face. A slide from one of my presentations:
From the article* "The influence of risk perception on biosafety
level 2 laboratory workers' hand to face contact behaviors"
Of the 93 subjects, 67 (72%) touched their face at least once,
ranging from 0.2-16.0 HFCs/ hr
- contact with the nose was (44.9%)
- forehead (36.9%)
- cheek/chin (12.5%)
- mouth (4.0%)
- eye (1.7%)
*Johnston JD1, Eggett D, Johnson MJ, Reading JC . The influence
of risk perception on biosafety level 2 laboratory workers' hand to
face contact behaviors . J Occup Environ Hyg 2014;11(9):625 32.
doi : 10.1080/15459624.2014.887206
Jeff
On Fri, Aug 20, 2021 at 11:16 AM Hunt, Alessandra <alehunt**At_Symbol_Here**msu.edu> wrote:
Hi Everyone,
I found the responses really interesting!
Coming from a "biological side" of lab safety this is my view:
- Wear disposable masks if working in biology labs where BSL-2 microorganisms are handled. If fabric masks are used then they should be laundered by the institution because like lab coats they should not be taken home. This is in the CDC recommendation: "Any face mask worn inside a laboratory area where personnel work with potentially infectious material should subsequently not be worn outside of that laboratory area." https://www.cdc.gov/coronavirus/2019-ncov/lab/lab-safety-practices.html
- For chemistry labs: I saw someone saying "if there is a splash", but if there is a splash that is a lab accident! If the mask was not there the splash would have been to the face! I also saw: "volatile compounds" but if someone is breathing in things with a mask they would be breathing it in in "normal days" (aka non-COVID-19 times) as well! So in that case they should be working in the fume hood. So in the case of a chemistry lab, in my opinion it doesn't really matter. Both masks would be ok: fabric or disposable. However, like someone said no one knows how often these masks are washed, so it is "nice" to have a clean mask (disposable) available.
You all forgive if I am being na=C3-ve and I appreciate your comments!
Alessandra