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<p class="MsoNormal">Hi Travis,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Many considerations: cost, code, feasibility, resiliency, scale etc. Too much to put in email, but I found this book is excellent (<a href="https://www.amazon.com/Semiconductor-Industry-Wafer-Exhaust-Management-ebook/dp/B07L6TKLXQ">https://www.amazon.com/Semiconductor-Industry-Wafer-Exhaust-Management-ebook/dp/B07L6TKLXQ</a>)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In general, the larger your facility the more it makes sense to segregate…Fabs often have several flavors (acid, solvent/VOC, heat, ammonia, perchloric, silane, gas cabinets etc). If your air permit requires (or you want to enable) centralized
scrubbers in the future, low concentrations and incompatible material mixing becomes a design constraint the pushes you towards separation.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Search the labnetwork archives, as this has come up in the past with great responses from the community…If you proceed with a combination system, the design team should conduct a risk assessment to document process assumptions. You want
to tell them your needs up front, not be told what can be accommodated after its built.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best,<o:p></o:p></p>
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<p class="MsoNormal" style="background:white"><b><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Nicholas Menounos, </span></b><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">PE, LEED AP</span><span style="font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">Associate Director of Infrastructure</span><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><b><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#212121"> </span></b><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><b><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#212121">MIT.nano</span></b><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><b><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">Massachusetts Institute of Technology</span></b><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">77 Massachusetts Ave, Bldg 12-5007</span><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">Cambridge, MA 02139</span><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">Cell: </span><span style="color:black"><a href="tel:+15089320938"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:blue">(508)
932-0938</span></a></span><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
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253-7234</span></a></span><span style="font-size:12.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black">Email: </span><a href="mailto:Menounos@mit.edu"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:blue">Menounos@mit.edu</span></a><span style="font-size:12.0pt;mso-ligatures:standardcontextual"><o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-family:"Calibri",sans-serif">From:</span></b><span style="font-family:"Calibri",sans-serif"> labnetwork <labnetwork-bounces@mtl.mit.edu>
<b>On Behalf Of </b>Massey, Travis<br>
<b>Sent:</b> Monday, February 24, 2025 9:24 PM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> [labnetwork] Combined or separate exhaust?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">Hi all,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">LLNL is planning a significant cleanroom expansion, and the question arose whether we
<i>need</i> separate exhaust for hoods and tools/gases, or if they can be combined into a single shared exhaust. Or do you have a single exhaust with 2+ exhaust fans pulling simultaneously, so there’s always
<i>some </i>exhaust air moving if one fan is down? The conventional wisdom around here has its share of holes, so I’m out to learn from the broader nanofab cleanroom community. How are your cleanrooms’ exhaust systems are configured, especially if you’ve
had to go down this cleanroom design rabbit hole?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">I’m also broadly open
<i>any</i> other lessons learned regarding provisioning exhaust or other utilities – whatever you feel like sharing. Too much information during the design phase is far better than too little.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><br>
Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">Travis Massey<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">Center for Micro and Nano Technology (CMNT)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">Lawrence Livermore National Laboratory (LLNL)<o:p></o:p></span></p>
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