How so Jay? I have worked with labs that used both these approaches without mishap, and without hood contamination (based on methylene blue screening). Of course both approaches need to managed properly (limited sample size, proper maintenance and cleaning, etc.), but I have always been comfortable with both in a lab setting. In fact, I first learned of the GFS glassware from John Long (perchlorate guru and technical director at GFS), at a CHAS symposium. James Kapin, MPH, CIH Advanced Chemical Safety 858-874-5577 Cell 619-990-5955 -----Original Message----- From: chemcon**At_Symbol_Here**juno.com [mailto:chemcon**At_Symbol_Here**juno.com] Sent: Tuesday, November 15, 2005 1:14 PM To: jim**At_Symbol_Here**CHEMICAL-SAFETY.COM Cc: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU Subject: Re: Questions About Perchloric Acid Sorry Jim, but anyone who follows your suggestions for handling perchloric acid is putting life and limb in danger. Jay Young On Tue, 15 Nov 2005 11:40:59 -0800 Jim Kapinwrites: > Hi Gordon - I will leave the argument about minimum quantities to > others, > but as far as I know, there are 2 good approaches to lab-scale > scrubbing for > perchloric work. The least expensive is "fume eradicator" glassware > from > GFS Chemicals that captures and scrubs vapors in water. An more > sophisticated (and expensive) alternative is to use the systems > developed > for Kjeldahl digestions that have built in capture and scrubbing > systems. > As I recall, Bucchi has a nice system. > > Let me know and I can dig up the relevant details - Jim > > James Kapin, MPH, CIH > Advanced Chemical Safety > 858-874-5577 Cell 619-990-5955 > > > -----Original Message----- > From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**LIST.UVM.EDU] On > Behalf Of > Gordon Miller > Sent: Monday, November 14, 2005 5:41 PM > To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU > Subject: [DCHAS-L] Questions About Perchloric Acid > Importance: Low > > I have one good question and two dumb ones. They are: > > What is a good chemistry and design for a scrubber to be used to > control emissions of perchloric acid from small scale heating > operations done in common hoods? > > Is there a quantity of perchloric acid that is so small that it can > be handled without benefit of a special hood, even if heated (Is > there a de minimis quantity)? > > What is the derivation of the NFPA 45 requirement that HClO4 not be > heated by flame or in an oil bath? I can guess, but I don't know. > > Please advise. "Inquiring minds want to know." > > Gordon Miller > Lawrence Livermore National Laboratory > P.O. Box 808 (L-379) > Livermore, California 94550 > (925) 423-8036 > Fax (925) 422-5176 > miller22**At_Symbol_Here**llnl.gov > >
Previous post | Top of Page | Next post