DCHAS-L Discussion List Archive

ERPG-1, -2, and -3 values for it are: Hexafluoropropylene (116-15-4) 
10 ppm 50 ppm 500 ppm. Old-fashioned refrigerants look very good when 
human toxicity is factored in...

At 9:45 AM -0700 4/26/07, Russell Vernon wrote:
>Dear Fellow Chemists,
>
>
>
>In California we are being required to test some of our fume hoods with
>a tracer gas. We are also being encouraged to reduce our greenhouse gas
>emissions.  The standard method, ASHRAE 110-1995, calls our sulfur
>hexafluoride as the tracer gas of choice. It takes about 0.5 to 1 kg of
>tracer gas for each test. SF6 has 23,900 times the global warming
>potential of CO2 largely dues to its stability and very long residence
>times in the atmosphere. ASHRAE 110-1995 allows for alternative tracer
>gases to be used but requires that they are similar in weight, stability
>and detection limits to SF6.
>
>
>
>The best alternative I've found so far is hexafluoropropene [116-15-4].
>The current director of our Air Pollution Research Center
>(www.aprc.ucr.edu  ) assures me that
>hexafluoropropene will hang around in the atmosphere only 4-5 days so
>will not have the dramatic negative environmental impact of SF6 (also it
>will not deplete the stratospheric ozone).
>
>
>
>I have found a local fume hood certifier that is set up to conduct the
>ASHRAE 100-1995 test who is willing to try a new gas, but his detector
>is calibrated to SF6.
>
>
>
>We contacted the manufacturer of his Q200 leak detector and they need a
>certified calibration gas source. Normally they use a 1% mix of gas in
>nitrogen, and fill a 0.6 liter bottle with it to a pressure of between 4
>and 10 bar.  The set the leak rate of the gas at either 1 x 10-7 or 1 x
>10-6 cc/sec, which corresponds to 0.1 and 0.2 ppm respectively.
>
>
>
>Can you recommend a lab, supplier or manufacturer that would be willing
>to create a certified mixture of 1% hexafluoropropene in nitrogen?
>
>
>
>(The manufacturer of the Q200 is in the UK so a European source may be
>the best.)
>
>
>
>Sincerely,
>
>-Russ
>
>Russell Vernon, Ph.D.
>UC System-wide Field Safety Working Group Chair
>http://ehs55.ehs.uci.edu/fieldsafe/index.jsp
>
>Laboratory / Research Safety Specialist & Integrated Waste Manager
>Environmental Health & Safety
>University of California, Riverside
>900 University Ave.
>Riverside, CA 92521
>
>russell.vernon**At_Symbol_Here**ucr.edu
>www.ehs.ucr.edu
>
>Direct: (951) 827-5119
>Admin: (951) 827-5528
>Fax: (951) 827-5122
>
>