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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='color:#1F497D'>Harvard FAS does both. We feed our Steam-to-Steam humidification boilers with 1 to 1.5 megohm RO water. These are AHU sized devices (up to 40,000 CFM) used for general ventilation. We feed a critical lab-specific ultrasonic (piezoelectric) duct-mounted humidifier (Stultz) with 18 megohm RO/DI. The RO/DI is piped in stainless by virtue of its corrosive properties as alluded to.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Tom Tribble<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><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>Morrison, Richard H., Jr.<br><b>Sent:</b> Friday, September 14, 2012 3:20 PM<br><b>To:</b> labnetwork@mtl.mit.edu<br><b>Subject:</b> [labnetwork] Steam Humidifier system question<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hi All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Facilities at my labs want to run 18megohm to a boiler for humidity control in another lab. I think it should be RO water as 18Megohm water is very corrosive. Any thoughts on this?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Their suggested design would draw 0.5gmp from my supply loop and return it to the DI tank? My belief is that this return water would be contaminated by the boiler system. What do you guys think?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rick<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Draper Laboratory<o:p></o:p></p><p class=MsoNormal>Group Leader Microfabrication Operations<o:p></o:p></p><p class=MsoNormal>555 Technology Square<o:p></o:p></p><p class=MsoNormal>Cambridge Ma, 02139-3563<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="http://www.draper.com">www.draper.com</a><o:p></o:p></p><p class=MsoNormal><a href="mailto:rmorrison@draper.com">rmorrison@draper.com</a><o:p></o:p></p><p class=MsoNormal>W 617-258-3420<o:p></o:p></p><p class=MsoNormal>C 508-930-3461<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>