About This Archive  | DCHAS-L 2022 Index   | DCHAS-L Yearly Index
person wearing a disposable face shield and surgical style mask

Check out Safety Emporium for your N95, N99, and face shield needs.

Previous by Date:
Subject: [DCHAS-L] Hood Servicing SOP
Date: Monday, April 11, 2022 at 7:35:34 PM
Author: Craig Merlic <merlic**At_Symbol_Here**CHEM.UCLA.EDU> 		Next by Date:
Subject: Re: [DCHAS-L] Hood Servicing SOP
Date: Tue, 12 Apr 2022 12:03:30 +0000
Author: Dr Bob

From: Ralph Stuart <ralph**At_Symbol_Here**rstuartcih.org>
Subject: Re: [DCHAS-L] Hood Servicing SOP
Date: Tue, 12 Apr 2022 07:37:40 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Message-ID: A44B4BB0-512E-44A2-8630-BCF98FA0ACAA**At_Symbol_Here**rstuartcih.org
In-Reply-To <90FC27A1-E57B-465F-8770-9994244AAE75**At_Symbol_Here**chem.ucla.edu>


> Usually the problem is a fan belt or motor that can be serviced on the 'clean' side.

I have addressed this question several times related to hood maintenance and each time a hood-specific review of the chemcial work done in the hood is necessary. This involves assessing what the possible contaminants of concern are likely to be present in the hood and ductwork and what sort of decontamination is appropriate. Given the wide variety of chemicals that could be used in a hood and the lack of information about quantities used, that can be a significant challenge. That approach doesn't lend itself to a policy statement very well.

Also, I'm not clear how the 'clean' side concept applies outside of radioactive materials hoods. Those hoods might have a HEPA filter in the duct to collect radioactive particles and the 'clean' side could be downstream of the HEPA filter? However, I don't know of any similar mechanism for chemical hoods, so I think everything downstream of the hood needs to be considered potentially contaminated (i.e. 'dirty').

- Ralph


Ralph Stuart, CIH, CCHO
ralph**At_Symbol_Here**rstuartcih.org

---
For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org
Follow us on Twitter **At_Symbol_Here**acsdchas

Previous post   |  Top of Page   |   Next post


The content of this page reflects the personal opinion(s) of the author(s) only, not the American Chemical Society, ILPI, Safety Emporium, or any other party. Use of any information on this page is at the reader's own risk. Unauthorized reproduction of these materials is prohibited. Send questions/comments about the archive to secretary@dchas.org.
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.