From: 8524828hau**At_Symbol_Here**COMCAST.NET
Subject: Re: [DCHAS-L] Chemical Fume Hoods
Date: January 26, 2012 9:19:48 PM EST
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: <3F30C6C05728AC48B01CD61A439F268626678F7E**At_Symbol_Here**>

As can easily be demonstrated with a simple smoke generator (or evaporating dry ice) a linear velocity of 150 f/m usually causes excessive turbulence/eddy currents that can cause escape of vapors from the hood to the user's breathing zone. Here are some examples of standards established by others. I choose these because they are information-rich with respect to explanations of different types of hoods (and their components), and the standard conditions under which linear velocity is measured. See comprehensive bibliography of regulations & stnds. Average 100 lfmp. 80-120 lfpm120 80-120 lfpm 80-120 lfpm >100 lfpm > 100 lfpm

David Haugen (retired)

From: "Patricia Peifer"
Sent: Thursday, January 26, 2012 2:46:04 PM
Subject: [DCHAS-L] Chemical Fume Hoods

I am not currently the person who is responsible for our lab fume hood testing, our metrology department does that. They wrote a procedure for this task but did not include an upper limit for face velocity. I was cited for this when we had an outside safety audit done, with the recommendation being that we have a upper limit for fpm of 150.

This made sense to me, my understanding was that an upper limit of 150 fpm (or even 120) was generally standard. I would like to learn more about ventilation and take over responsibility of the fume hood testing at my facility.

My question is:
• Is training highly recommended or even required to test chemical fume hoods?
• Does anyone have a recommendation for training?
• Should I indeed be looking at 150 fpm as an upper limit? I have looked at ANSI, NRC, etc., but have not purchased the actual documents.

Thanks you,

Pat Peifer, CHO
Safety and Chemical Hygiene Specialist
West Pharmaceutical Services
101 Gordon Drive
Lionville, PA 19341

Find West on Twitter and LinkedIn.

The contents of this message are confidential and may be privileged. If you have received this message in error, please permanently delete it, along with any files that may be attached to this message, without reading, printing, copying, forwarding or otherwise distributing it. Please notify the sender of the error immediately so that we can prevent it from happening again.

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
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.