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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Iulian, <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I agree with Dennis from UofM. The scenario that is called a “catastrophic release” with RFO’s in place would require the cylinder to be dropped and the valve broken off or the stem damaged. This essentially can’t take place in the confines of a gas cabinet but is much more likely to happen just outside the cabinet where a cylinder could fall. In this case a “catastrophic release” scrubber connected to the cabinet would do very little good since the release is not contained within the cabinet. We wasted a great deal of money and precious floor space on two of these units in our first cleanroom. A word of caution; you may also find it very hard to make any argument against a “safety” item once it has been suggested.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Mark Heiden <br>UC Riverside <br>Center for Nanoscale Science and Engineering <br>NanoFab Cleanroom Manager <br>(951) 827-2551 <br>mheiden@engr.ucr.edu </span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> labnetwork-bounces@mtl.mit.edu [mailto:labnetwork-bounces@mtl.mit.edu] <b>On Behalf Of </b>Dennis Schweiger<br><b>Sent:</b> Monday, September 23, 2013 11:57 AM<br><b>To:</b> Iulian Codreanu<br><b>Cc:</b> Fab Network<br><b>Subject:</b> Re: [labnetwork] catastrophic release scrubbers<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Iulian,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I figured everyone would want to see this response to your question as well.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>We looked at the catastrophic release scenario when we designed the expansion for our fab here at UofM, and by installing a restrictive flow orifice in the cylinder (0.010"), minimizing the fill quantity (short filling the cylinder to considerably less than a maximum), and maximizing the dilution at the tip of the exhaust fans (using Strobic fans), we were able to find a workable/acceptable solution. It would take a "huge" abatement system to handle what could essentially never happen. It made more sense to put our capital dollars into something that worked for everything (the additional exhaust dilution), and share that capacity across the entire fab.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Take care,</span><o:p></o:p></p></div><div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><div><p class=MsoNormal>Dennis Schweiger<o:p></o:p></p></div><div><p class=MsoNormal>University of Michigan/LNF<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><div><p class=MsoNormal>734.647.2055 Ofc<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><div><p class=MsoNormal>"People can be divided into 3 groups - those that make things happen, those that watch things happen, and those that wonder what happened." Within which group do you belong?<o:p></o:p></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p><div><p class=MsoNormal>On Tue, Sep 17, 2013 at 4:42 PM, Iulian Codreanu <<a href="mailto:codreanu@udel.edu" target="_blank">codreanu@udel.edu</a>> wrote:<o:p></o:p></p><p class=MsoNormal>Dear Colleagues,<br><br>I am writing to ask for input on the use individual catastrophic release scrubbers for gas cabinets. They are being proposed to reduce the risk of toxic gases from the under-design toxics/pyrophorics bunker into the building air handlers.<br><br>If anyone is using these or has considered using them I would very much like to hear your thoughts on the subject.<br><br>Thanks a lot!<br><br>Iulian<br><br>-- <br>iulian Codreanu, Ph.D.<br>Director of Operations, UD NanoFab<br>University of Delaware<br>149 Evans Hall<br>Newark, DE 19716<br><a href="tel:302-831-2784" target="_blank">302-831-2784</a><br><br><br>_______________________________________________<br>labnetwork mailing list<br><a href="mailto:labnetwork@mtl.mit.edu" target="_blank">labnetwork@mtl.mit.edu</a><br><a href="https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork" target="_blank">https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>