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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">John –<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The issue here is not so much particles as airborne molecular contaminants (AMCs). If the work that you are doing is sensitive to these airborne materials,
then this is definitely a bad idea. If your work is sensitive only to particles, you can probably get away with this approach.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">At the BNC, we went to extremes in this regard. We use specialized clean-steam generators (heat exchangers with campus steam) and our full ultrapure water.
This minimizes – virtually eliminates – AMCs from the humidification process. It is a relatively expensive approach, but we also operate at ISO 3 (Class 1) as we have several very sensitive areas of research.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I would think that using pure RO water would be a good compromise, but it really depends on what your process and device sensitivity is.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">John<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>
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<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">John R. Weaver<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">Strategic Facilities Officer<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">Birck Nanotechnology Center<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">1205 West State Street<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">West Lafayette IN 47907<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">(765) 494-5494<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D"><a href="mailto:jrweaver@purdue.edu">jrweaver@purdue.edu</a><o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span style="font-size:9.0pt;font-family:"Cambria","serif";color:#1F497D">nano.purdue.edu<o:p></o:p></span></i></b></p>
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<p class="MsoNormal" style="margin-left:.5in"><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>John Nicholson<br>
<b>Sent:</b> Wednesday, February 04, 2015 5:22 PM<br>
<b>To:</b> Labnetwork<br>
<b>Subject:</b> [labnetwork] Humidification System Design<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">Hello all,<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"> We are currently in a design review process for a new class 1000 clean room on campus and the design architects have come up with a scheme that mixes RO steam with the existing building steam (containing
softeners and whatever minerals the local city water has) to humidify the clean room. I am of the opinion this is a bad idea. Your opinions would be greatly appreciated as well as references to any design standards (ASHRAE?) you may know of for this type of
humidification system.<o:p></o:p></p>
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Regards,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in">
John<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New";color:#212121;background:#F7F7F7">-- </span><span style="font-size:10.0pt;font-family:"Courier New";color:#212121"><br>
<span style="background:#F7F7F7">John Nicholson</span><br>
<span style="background:#F7F7F7">Nanofabrication Laboratories Manager</span><br>
<span style="background:#F7F7F7">MassNanoTech Nanofabrication Facility</span><br>
<span style="background:#F7F7F7">Conte Center for Polymer Research, Rm. B111</span><br>
<span style="background:#F7F7F7">University of Massachusetts Amherst</span><br>
<span style="background:#F7F7F7">120 Governor's Drive</span><br>
<span style="background:#F7F7F7">Amherst,MA 01003-9305</span><br>
<span style="background:#F7F7F7">Phone: 413-545-2772</span><br>
<span style="background:#F7F7F7">Fax: 413-577-0165</span></span><o:p></o:p></p>
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