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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Interesting project, Hank.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>This brings back fond memories of my time at Nuclear Biological Chemical Defense school during my youth. Tear gas tastes very differently than bear spray. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Is the designed length of occupancy one week for wild fires or one year for plagues? Like the military, I usually prefer one separate component for each separate task. You may only need one or the other turned on at any given time. The two media likely have different times before saturation. But as long as both the scrubber media and charcoal are in separate modules that can switched out for fresh without affecting the other then it should be okay. Another issue with a single component is having backup power and forced air propulsor in case the single unit fails, resulting the failure of both the scrubber and the filter. If the forced air propulsors in both separate units are the same then this allows you to have greater backup capability. Depending on how long you plan to be self-contained you may also want some type of electrostatic ionizer and O3 generator to sanitize the breathing air. Just don't breath in a high level of O3 for more than a short (minutes) length of time.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>There are other members of this group who have greater experience with long stay self-contained life support systems, particularly those who spent time with nuke boats or spacecraft.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Sorry, I do tend to blather on.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Tim<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Personal_Submersibles [mailto:personal_submersibles-bounces@psubs.org] <b>On Behalf Of </b>hank pronk via Personal_Submersibles<br><b>Sent:</b> Sunday, April 12, 2020 4:54 PM<br><b>To:</b> Personal Submersibles General Discussion <personal_submersibles@psubs.org><br><b>Subject:</b> [PSUBS-MAILIST] scrubber<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>Hi All, I am starting a project tomorrow, I am building an underground emergency shelter that is fully self contained. I am installing a CO2 scrubber. I want a charcoal filter as well, and I would like the CO2 scrubber to do both jobs. Is there any reason I can not mix activated charcoal with absorbent. Is it better to have separate layers of media?<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>Hank<o:p></o:p></span></p></div></div></div></body></html>