From: Richard Palluzi <000006c59248530b-dmarc-request**At_Symbol_Here**LISTS.PRINCETON.EDU>
Subject: Re: [DCHAS-L] Acid Stills...
Date: Sat, 30 Mar 2019 06:19:27 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: 00b301d4e6e2$0e9bb5b0$2bd32110$**At_Symbol_Here**

The damage to you hood system is likely to be significant over a short period of time as neither hood nor the duct work is designed for acid condensation. Using a laminar flow hood for such a high volume operation also sound like an easy recipe for a significant exposure problem.


My recommendation is:


  1. You need a detailed hazard analysis and risk assessment by trained individuals and not just the researcher. I feel confident they will have the same concerns as mentioned above.
  2. This type of work should be done in a 100 fpm face velocity hood not a laminar flow hood nor a zero pressure enclosure which I assume is either a dry box or simply an enclosure either of which are truly awful ideas.
  3. The operation needs a robust and well designed condenser system to avoid major damage to the hood, ductwork and fans as well as to reduce exposure levels. This type of system, while conceptually easy to design, is open so poorly designed and sized as to be useless. So it should be reviewed in detail as part of step 1.


This is one of those research operations that tends to fly under the radar until the lab starts to fall apart and people start to report in sick.


Richard Palluzi



Pilot plant and laboratory consulting, safety, design,reviews, and training


Richard P Palluzi LLC

72 Summit Drive

Basking Ridge, NJ 07920




From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> On Behalf Of Margaret Rakas
Sent: Friday, March 29, 2019 2:25 PM
Subject: [DCHAS-L] Acid Stills...


We are in the early stages of preparing for a new researcher who plans to distill various mineral acids using a commercially available acid still.  This is totally new ground for me/the college--and I am looking for guidance, SOPs, 'What I wish we knew then' stories.


Also we are constructing a soft-sided clean room for said researcher, who will add two positively pressured laminar flow hoods and 1-2 "zero pressure" enclosures.  My understanding currently is that the acid still will go in one of the zero-pressure enclosures (which is a higher level of 'clean' than the outer 'clean' room).  The soft-sided clean room will be contained within a larger, negatively pressured lab.


If you have any experience with a setup like this, I would love to hear about it whether that's an email to the listserv, or we arrange a phone call or whatever.


Many thanks!



Margaret A. Rakas, Ph.D.
Manager, Inventory & Regulatory Affairs
Clark Science Center
413-585-3877 (p)

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