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<p class="MsoNormal">Devin,<o:p></o:p></p>
<p class="MsoNormal"> I would suggest getting a baseline of your entire fab by a company that specializes in this. Once a year, we have our fab re-certified and as they perform this, they examine the entire HEPA coverage with a sonic detector that will show
leaks, and problem areas. This company hires a HEPA installation/service person to follow them around to fix problems as they are identified.<o:p></o:p></p>
<p class="MsoNormal">After you have this baseline map, I would also recommend a permanent particle counter in the middle of all the chase areas if your clean room is a sidewinder, or in the floor if it’s a ballroom style raised floor. This will provide real
time averaging and will provide feedback if you wish to have a closed loop system that communicate to the HEPA fan VFD, This type of arrangement will be capable of slowing down your air changes/Hr. during periods of inactivity. This is a tremendous energy
conservation measure as well as having the ability to speed up the HEPA air during higher particulate generation times.<o:p></o:p></p>
<p class="MsoNormal">I realize the large expense of doing this but if you want to get serious about maintaining a truly clean room without just dumping money on other measures, it’s a good way to go. I am curious to hear what other fabbers use as a method.<o:p></o:p></p>
<p class="MsoNormal"> Best of luck,<o:p></o:p></p>
<p class="MsoNormal"> Equipment Dood<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:14.0pt">Steve Paolini<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">Principal Equipment Engineer<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">Harvard University Center for Nanoscale Systems<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">11 Oxford St.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">Cambridge, MA 02138<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">617- 496- 9816<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">spaolini@cns.fas.harvard.edu<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt">www.cns.fas.harvard.edu</span><span style="font-size:14.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> labnetwork-bounces@mtl.mit.edu <labnetwork-bounces@mtl.mit.edu>
<b>On Behalf Of </b>Devin Fortier<br>
<b>Sent:</b> Wednesday, September 25, 2019 11:49 AM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> [labnetwork] Stationary Particle Counters<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Dear Colleagues,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">We are looking to improve the way we do particle counts in our cleanroom and are looking at installing multiple stationary particle counters as a solution. We would also want these devices to tie in with our building monitoring system
that uses BACnet. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">We currently have a portable particle counter that is moved to various set locations and left to take its measurements. This is being done by a staff member and the whole procedure takes up almost half a day of one person's time per week.
Aside from taking so much time, the counter is cumbersome and gets in the way of our users in the lab. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">My question to the group is what are you currently using for your particle counts? Does anyone use stationary particle counters and process the data to get an average over the whole cleanroom area?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank you,<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Devin Fortier</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Systems/Infrastructure Specialist</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">University of Alberta - nanoFAB</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">W1-028A ECERF Building</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">9107 - 116 Street</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Edmonton, Alberta</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Canada T6G 2V4
</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black"><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.nanofab.ualberta.ca_&d=DwMFaQ&c=WO-RGvefibhHBZq3fL85hQ&r=-H4Z_jeDfTYjnKPXor15vLwzBllmg8gFrb9m_k9OGks&m=mc7Q3G2DP5uG_q1s2-5QJgVjUst8hvgaQ00NEZhrcbQ&s=iksD82WAh8TdNhNP_B3a0oqer7moRv2_PtOUOF-8msQ&e=" target="_blank"><span style="color:#1155CC">www.nanofab.ualberta.ca</span></a>
Ph: 780-868-6480</span><o:p></o:p></p>
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