Based on the responses summarized below, I think that my conservative inclination with regard to ductless fume hoods is generally shared, although it sounds like there are some potential uses out there. I think that Monona Rossol's suggestion of collecting more data (and submitting a paper to the CHAS Journal) is a good one. Thanks to everyone who replied. - Ralph == Subject: FW: Ductless fume hoods policy? Date: Thu, 28 Apr 2005 13:17:02 -0400 From: "Reinhardt, Peter \(Environment Health and Safety\)"
I think a ductless fume hood would be OK only when handling fine particles and turbulence is not permissible. -- Pete ==== Date: Thu, 28 Apr 2005 12:33:40 -0500 From: Alton Simpson Organization: The University of Memphis Our Chemical Hygiene Plan says, "Ductless hoods are considered unsuitable for materials other than nuisance vapors and dusts which do not present fire or toxicity hazards." Our radiation safety committee, however, does allow approved ductless hoods equipped with carbon filter for use in I-125 labeling. Al Alton Simpson, CHMM Director, Environmental Health and Safety The University of Memphis ==== Date: Thu, 28 Apr 2005 13:34:44 -0400 From: "Wawzyniecki Jr, Stefan" Subject: Re: Ductless fume hoods policy? We do not allow them for the following reasons: 1. No way of enforcing the "no more than 50cc of a solvent" dispensing rule 2. Solvents such as methylene chloride are not captured efficiently 3. Usually a maintenance program for scheduled replacement of the filters is not established and / or followed 4. Departments may use the excuse that they can't afford replacement filters, and Facilities will claim that replacements don't come out of their budget either. 5. Monitoring of the exhaust is usually not done, and it is an added cost as well. -Stefan Wawzyniecki UConn ==== Date: Thu, 28 Apr 2005 From: "David D Lee" Inquiring minds? Or someone who's looking for a way around the current policy? Why not just use a normally exhausted lab hood in the first place? Or are they trying to avoid the expense of installing one? I'm just curious. Personally, I have no use for ductless hoods. David D. Lee, MIS, CIH, CSP Safety Specialist University of Nevada, Reno EH&S Dept/MS 328 Reno, NV 89557 ==== Date: Thu, 28 Apr 2005 14:03:58 -0400 From: "Margaret Rakas" Subject: Re: [DCHAS-L] Ductless fume hoods policy? I have, and would, fight tooth and nail against having them. First, charcoal filters will preferentially absorb and desorb various solvents; you can't quite know what you're capturing and what you aren't. And manufacturer change-out recommendations? Forget it, they aren't going to touch that issue and you're flying blind. Lastly, when has anyone ever bought a hood (other than hopefully a perchloric acid hood) to just use for one or two chemicals? Even if the intentions are there and pure at the beginning, suddenly an idea takes off and whoosh! So my only policy (which might not help much) is "Let's find a better way to do this." I would be very interested in the results if anyone has done vapor absorption and/or air sampling for these types of devices; data would be extremely helpful in establishing policies but I haven't found any. The above are my personal opinions only. Margaret Margaret A. Rakas, Ph.D. Manager, Inventory & Regulatory Affairs Clark Science Center Smith College ==== Date: Thu, 28 Apr 2005 14:04:08 -0400 From: "Haugen, Bob" SEFA 1 is beginning to look at this area, but most people who design hoods, like me, use a slightly modified saying: "Keep your friends close, and give your enemies ductless fume hoods." Dr. Bob Haugen Kewaunee ==== From: "George H. Wahl, Jr." Subject: Re: Ductless fume hoods policy? Ralph, Our new teaching labs have them on the desk top, as well as "normal" 6-8' hoods along one wall. Since we're also using "Micro Scale" we have no policy of which I'm aware. I'm copying our Lab Director to see if she has ever stated a "policy" on the matter. Any suggestions of folks I might harass to get a few more speakers on "Teaching Safety" for DC mtg? We're looking for folks who are trying new approaches; or may have recently done an evaluation of what they have been doing. Could also be some new software, or applications of software to Safety instruction. Just digging! George ==== From: Robert R Mako Date: Thu, 28 Apr 2005 15:30:29 -0700 We also avoid them, but have used them based on need, capture efficiency, filter life, and ability to establish a reliable PM process. Bob Mako, CIH, CSP EHS Manager Raytheon Goleta, CA rrmako**At_Symbol_Here**raytheon.com ==== From: Harry J. Elston Date: Thu, 28 Apr 2005 Ralph, Talk with Lou DiBerardinis at MIT. I was a complete anti-ductless guy not so long ago, but after speaking with Lou and Doug Walters, I can see some useful applications. His e-mail is: louDiB**At_Symbol_Here**mit.edu Harry +++++++++++++++++++++++++++++++++++ Harry J. Elston, Ph.D., CIH Principal - Midwest Chemical Safety www.midwestchemsafety.com helston**At_Symbol_Here**midwestchemsafety.com 217.971.6047 Editor, Chemical Health & Safety www.elsevier.com/locate/chs http://membership.acs.org/c/chas/ ==== From: "Bob Peck" Subject: RE: [DCHAS-L] Ductless fume hoods policy? Date: Thu, 28 Apr 2005 22:08:05 -0500 Unless you are using an absorbent bed with a service life indicator specific to the liquid/vapor being used, a ductless hood should only be used for dusts that don't sublime. Use of any volatile material with this type hood should be gauged by room air changes, with the understanding that you are contaminating the run air by the process you run. That is generally a very bad idea from a personnel exposure point of view! Bob Peck Eagle's Rest Consulting Services, LLC ==== Date: Fri, 29 Apr 2005 12:17:27 -0400 From: mark.kidd**At_Symbol_Here**srnl.doe.gov Subject: Re: Ductless fume hoods policy? In NFPA 45, "Fire Protection for Laboratories Using Chemicals," A.6.4.1: "Ductless laboratory hoods that pass air from the hood interior through an absorption filter and then discharge the air into the laboratory are only applicable for use with nuisance vapors and dusts that do not present a fire or toxicity hazard." I think acetone pouring would not be allowed in a ductless fumehood. Mark Kidd Chemical Hygiene Officer Savannah River National Laboratory Telephone: 803.725.4576 Fax: 803.725.1660 Email: mark.kidd**At_Symbol_Here**srnl.doe.gov
Previous post | Top of Page | Next post