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<p>Hi all -</p>
<p>Cleanroom filters dating from the original build in 1986 at SNF
were replaced in 2012. There were two unanticipated benefits.
First, the sound levels dropped -- a lot of people wondered if the
laminar flow was really on. It certainly made for a more pleasant
work environment. Second, the electrical use in the building
dropped. It's hard to tell exactly what was attributable to the
HEPA changeout because we also reduced some flow rates as well,
but initial estimates were around 12% total reduction in
electrical energy use versus before the project.</p>
<p>So, there may be additional reasons for replacing HEPA filters,
including the possibility that energy conservation programs may
help with project costs.</p>
<p>Mary<br>
</p>
<p><br>
</p>
<p>-- </p>
<pre class="moz-signature" cols="72">Mary X. Tang, Ph.D.
Managing Director
Stanford Nanofabrication Facility
Paul G. Allen Building
420 Via Palou Mall
Stanford, CA 94305
<a class="moz-txt-link-freetext" href="https://snf.stanford.edu">https://snf.stanford.edu</a>
<a class="moz-txt-link-abbreviated" href="mailto:mtang@stanford.edu">mtang@stanford.edu</a></pre>
<div class="moz-cite-prefix">On 2/16/2022 11:44 AM, Collins, Deon
wrote:<br>
</div>
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<div class="WordSection1">
<p class="MsoNormal">Deon Collins from Holonyak lab University
of Illinois<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Our facility has replaced HEPA filters lab
independent as well as the entire cleanroom once. Our HEPA’s
filter are molded into the supply side(ceiling) with no
temporary seals. The filters are bolted into the ceiling as
well as caulked into the structure itself, so replacement is
labor intensive. <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Do you have any particle count trends to go
by? Do you have any Magnehelic trends to go by? If you are
seeing a high delta between the two in conjunction with high
particle counts it is time.
<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">If your maintenance group has done a good
job of maintaining the pre filters HEPA filters will see
prolonged life. If the pre filters have been ignored the HEPA
filters will suffer.
<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">As mentioned below your ductwork integrity
has a profound effect on your system. You could see an
individual lab with excellent results while the lab adjacent
is suspect.
<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<div>
<p class="MsoNormal"><b><span
style="color:#002060;text-transform:uppercase">Deon D.
Collins</span></b><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#002060"><br>
<i>FACILITY MANAGER</i><br>
Holonyak Lab</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#002060">University of
Illinois at Urbana-Champaign</span><span
style="color:#1F497D"><br>
</span><span style="color:#13294B">208 N Wright St Rm. 248 |
2250</span><span style="color:#1F497D"><br>
</span><span style="color:#13294B">Urbana, IL 61801</span><span
style="color:#1F497D"><br>
</span><span style="color:#13294B">217-300-7531 | </span><a
href="mailto:deonc69@illinois.edu" moz-do-not-send="true"><span
style="color:#0563C1">deonc69@illinois.edu</span></a><span
style="color:#1F497D"><br>
<br>
<br>
</span><a href="http://illinois.edu/" moz-do-not-send="true"><span
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style="color:#1F497D"><br>
<br>
</span><i><span style="color:#666666">Under the Illinois
Freedom of Information Act any written communication to
or from university employees regarding university
business is a public record and may be subject to public
disclosure.
</span></i><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><b><span
style="font-size:10.0pt;color:#A3238B">Life is not about
watching other people live it. It’s about you living
your own!</span></b><o:p></o:p></p>
</div>
<p class="MsoNormal"> <o:p></o:p></p>
<div>
<div style="border:none;border-top:solid #E1E1E1
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> labnetwork <<a
href="mailto:labnetwork-bounces@mtl.mit.edu"
moz-do-not-send="true" class="moz-txt-link-freetext">labnetwork-bounces@mtl.mit.edu</a>>
<b>On Behalf Of </b>Reger, Ronald K<br>
<b>Sent:</b> Tuesday, January 25, 2022 2:30 PM<br>
<b>To:</b> <a href="mailto:labnetwork@mtl.mit.edu"
moz-do-not-send="true" class="moz-txt-link-freetext">labnetwork@mtl.mit.edu</a><br>
<b>Subject:</b> [labnetwork] HEPA/ULPA Filter Experience?<o:p></o:p></p>
</div>
</div>
<p class="MsoNormal"> <o:p></o:p></p>
<div>
<p class="MsoNormal">Dear Colleagues,<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">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. <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">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?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">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.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Thanks very much for your information.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Ron <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><b><span
style="font-size:14.0pt;font-family:"Microsoft
PhagsPa",sans-serif;color:#1F497D">Ron Reger</span></b><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><i><span
style="font-size:10.0pt;color:#1F497D">Engineering
Manager</span></i><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-size:9.0pt;color:#1F497D">Birck Nanotechnology
Center | Room 2289 |</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><b><span
style="font-size:9.0pt;color:#1F497D">Office:</span></b><span
style="font-size:9.0pt;color:#1F497D">
</span><span style="font-size:9.0pt;color:#0070C0">765.494.6667
</span><span style="font-size:9.0pt;color:#1F497D">|
<b>Email:</b> </span><a href="mailto:rreger@purdue.edu"
moz-do-not-send="true"><span
style="font-size:9.0pt;color:#0070C0">rreger@purdue.edu</span></a><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="color:#1F497D">Wiki: </span><a
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<p class="MsoNormal"><span style="color:#1F497D">iLabs: </span><a
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style="font-size:12.0pt;color:#1F497D">
</span></b><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
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<br>
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