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<div>Dear Colleagues,</div>
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<div>The cleanroom here at the Purdue Birck Nanotechnology Center is in its 17th year, and we're starting to see increased frequency on some typical and expected maintenance items. And while we haven't had any catastrophic failures yet in our HEPA & UPLA filters
we are wondering when they may need some serious attention/replacement. All along we've had to replace an occasional filter panel due to some deterioration of a seal or maybe an inadvertent puncture, but we haven't had any wholesale replacement of complete
banks or bays yet. </div>
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<div>We're wondering what other nanofabs have experienced in terms of HEPA/ULPA filter replacements? Is there a target date (~ 20 years, 25 years?) at which filters fail and entire bays are replaced? Are seals degrading at a certain time as shown with increasing
particle counts? Have different nanofabs experienced vastly different durations for the quality of filtration?</div>
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<div>Any insight into filter degradation & replacement experience would be greatly appreciated as we plan for the next few years of maintenance items in our fab.</div>
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<div>Thanks very much for your information.</div>
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<div>Ron </div>
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<div><font face="Microsoft PhagsPa" size="4" color="#1F497D"><span style="font-size:14pt;"><b>Ron Reger</b></span></font></div>
<div><font size="2" color="#1F497D"><span style="font-size:10pt;"><i>Engineering Manager</i></span></font></div>
<div><font size="2" color="#1F497D"><span style="font-size:9pt;">Birck Nanotechnology Center | Room 2289 |</span></font></div>
<div><font size="2" color="#1F497D"><span style="font-size:9pt;"><b>Office:</b><font face="Calibri"> </font> <font color="#0070C0">765.494.6667 </font>| <b>Email:</b> <a href="mailto:rreger@purdue.edu"><font color="#0070C0"><u>rreger@purdue.edu</u></font></a></span></font></div>
<div><font color="#1F497D">Wiki: <a href="https://wiki.itap.purdue.edu/display/BNCWiki"><font color="#0070C0"><u>https://wiki.itap.purdue.edu/display/BNCWiki</u></font></a></font></div>
<div><font color="#1F497D">iLabs: <a href="https://purdue.ilabsolutions.com/homepage/"><font color="#0563C1"><u>https://purdue.ilabsolutions.com/homepage/</u></font></a><font size="3"><span style="font-size:12pt;"><b> </b></span></font></font></div>
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