Thanks, Larry for finding the CCS reference. I can speak about the CCS document since my subcommittee wrote it.
The reason that UV disinfection is not mentioned in the CCS document is that the efficacy is questionable and highly dependent of a number of factors:
· “Time on contact”
· UV wavelength (UV-C, 100-280 nm)
· UV intensity (power per unit area on the goggle)
UV lights used in disinfection systems require substantial maintenance in order to keep the intensity and wavelength constant which means a frequent lamp change-out and therefore higher system cost. Just because the lamp is “on” does not mean that it has the same intensity, intensity distribution (throughout the cabinet) or wavelength that it had when first installed. Systems degrade with time, and high-intensity, short-wavelength lights are no exception. (For those familiar with photoionization detectors, think of the lifespan difference between a 10.6eV lamp – about 12-18 months vs. an 11.7 eV lamp – about 3-6 months).
Also there’s the time/hassle/cost factor since very few academic institutions have robust preventative maintenance programs or are willing to spend the money for a replacement schedule. It’s been my experience that people want a system they (1) they can install and forget about (2) low maintenance and (3) it works well every time. That will not be a UV disinfection system.
Here’s a paper on the questionable efficacy of UV disinfection: Nocker, Andreas, Sossa, Katherine E., Camper, Anne K. “Molecular monitoring of disinfection efficacy using propidium monoazide in combination with quantitative PCR.” J. Microbiol. Methods; 2007, 70, 252-260.
In contrast to that paper, there are a few articles regarding hospital settings that have had success using UV-C for disinfection:
http://www.infectioncontroltoday.com/topics/ultraviolet-light.aspx
The facility owner needs to make their own call on it of course, but it should be an informed call. My recommendation is a high-quality dish soap (Dawn is my favorite), water and a microfiber cloth.
Harry
++++++++++++++++++++++++++++
Harry J. Elston, Ph.D., CIH
Midwest Chemical Safety LLC
Twitter: **At_Symbol_Here**MidwestChemSafe
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From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Laurence Doemeny
Sent: Tuesday, May 13, 2014 8:12 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] ? Re Safety Glasses and UV Cabinets
The ACS Committee on Chemical Safety recommends:
This is the CDC discussion for decontamination and disinfection.
http://www.cdc.gov/biosafety/publications/bmbl5/BMBL5_appendixB.pdf
UV disinfection is not mentioned in either citation.
-----Original Message-----
From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Wilhelm, Monique
Sent: Tuesday, May 13, 2014 12:22 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: [DCHAS-L] ? Re Safety Glasses and UV Cabinets
Hello everyone,
One of my colleagues is interested in knowing what other University Biology labs require in terms of eye protection in their labs with low splash potential due to minute quantities handled and how they go about it. Does anyone have any experience with providing safety glasses and a UV cabinet for disinfection for a class room?
Thank you for your wisdom,
Monique Wilhelm
Laboratory Supervisor/Adjunct Lecturer/Chem Club Co-Advisor Department of Chemistry & Biochemistry University of Michigan-Flint Flint, MI 48502
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