EPISODE · May 18, 2026 · 1H 37M
Beyond Particulates: How Gas Phase Filtration Protects Everything From Data Centers to Lungs 117
from Air Quality Matters · host Simon Jones
This week, we sit down with Christopher Mueller, Global Director of the High Purity Segment at AAF International (American Air Filters), to explore a question that fundamentally challenges how we think about indoor air quality: What if the single biggest gap in our approach to healthy buildings isn't particulate filtration—but our complete failure to address the invisible chemical soup we're breathing every single day? Chris brings over 40 years of deep expertise in environmental air quality and gas phase air filtration. With more than 200 peer reviewed papers, hundreds of seminars, and co authorship of major industry handbooks including the NAFSA Air Filtration Handbook and ASHRAE standards, Chris has testified at OSHA on indoor air quality standards and consulted with governments worldwide. He is the former chair of ASHRAE 145, which developed the first standard for assessing gas phase air filtration media performance, and remains a member of key technical committees shaping the future of air cleaning globally. Key Topics Discussed: The Fundamental Difference: Particulate filtration is catching. Gas phase filtration is reacting. Gases move by diffusion, from high to low concentration, and removing them requires adsorption—getting molecules out of the air and onto the surface of materials like activated carbon, alumina, or zeolites. Unlike particle filters, gas phase filters don't fill up. They run out. They lose effectiveness over time, and there's no pressure gauge to tell you when. Surface Area Is Everything: Most activated carbons have around 1100 square meters per gram of surface area. That's not the exterior of the pellet. That's the interior pore structure. Volatile organic compounds get inside, condense back into liquid form, and stay there. The physics of adsorption depend on molecular weight, concentration, residence time, and contact efficiency. You need the air to touch the adsorbent before it exits the filter. One Filter Won't Do It All: You can't use one type of gas phase media to remove everything. Basic activated carbon handles many organic compounds. Acid gases like sulfur dioxide require chemically treated carbon. Ammonia requires another type entirely. Think of it like particulate filtration: pre filter, intermediate filter, final filter. Same logic applies to chemicals. The Four Global Markets: Corrosion control accounts for 60 to 65 percent of the global gas phase filtration market, driven by electronics manufacturing, data centers, and industrial facilities where chemical contamination voids equipment warranties. Wastewater odor control is second. Indoor air quality in commercial buildings is third. Airborne molecular contamination in semiconductor manufacturing is fourth. The total global market is approximately $2 billion and growing at 5.5 percent annually. GUEST: Christopher Mueller Global Director, High Purity Segment, AAF International https://www.linkedin.com/in/chrismullerconsulting/ AAF International https://www.aafintl.com/ The Air Quality Matters Podcast in Partnership with Particles Plus https://particlesplus.com/ Eurovent (https://www.eurovent.eu/) - Aico (https://www.aico.co.uk/) - Lindab (https://www.lindab.ie/) The One Take Podcast in Partnership with SafeTraces (https://www.safetraces.com/) and Inbiot (https://www.inbiot.es/?utm_campaign=simon&utm_source=airqualitymatters&utm_medium=podcast) - Farmwood (https://farmwood.co.uk/) Do check them out in the links and on the Air Quality Matters Website. (https://www.airqualitymatters.net/podcast) If you haven't checked out the YouTube channel its here (https://www.youtube.com/@airqualitymatters-SimonJones). Do subscribe if you can, lots more content is coming soon. Chapters 00:00:00 Introduction: Meeting the Gas Phase Air Cleaning Guru 00:02:51 The Fundamental Difference: Particulate vs Gas Phase Filtration 00:09:29 The Science of Adsorption: How Gas Phase Filters Actually Work 00:17:10 The Swiss Cheese Approach: Multi-Stage Gas Phase Filtration 00:23:20 Form Factors and Physical Products: From Pleats to Packed Beds 00:28:00 Precision and Specificity: Can You Target Individual Chemicals? 00:34:20 The Four Markets: Where Gas Phase Filtration Is Applied Today 00:38:24 Corrosion Control: The Hidden Giant of Gas Phase Filtration 00:44:00 Indoor Air Quality and the IAQP Opportunity 00:48:38 The Commercial Reality: Why Gas Phase Is Still a Hard Sell 01:13:49 Materials and Sustainability: What Is Activated Carbon Made From? 01:24:13 The Path Forward: Education, Standards, and Market Evolution 01:36:35 Closing Thoughts: Making the Invisible Visible
What this episode covers
This week, we sit down with Christopher Mueller, Global Director of the High Purity Segment at AAF International (American Air Filters), to explore a question that fundamentally challenges how we think about indoor air quality: What if the single biggest gap in our approach to healthy buildings isn't particulate filtration—but our complete failure to address the invisible chemical soup we're breathing every single day? Chris brings over 40 years of deep expertise in environmental air quality and gas phase air filtration. With more than 200 peer reviewed papers, hundreds of seminars, and co authorship of major industry handbooks including the NAFSA Air Filtration Handbook and ASHRAE standards, Chris has testified at OSHA on indoor air quality standards and consulted with governments worldwide. He is the former chair of ASHRAE 145, which developed the first standard for assessing gas phase air filtration media performance, and remains a member of key technical committees shaping the future of air cleaning globally. Key Topics Discussed: The Fundamental Difference: Particulate filtration is catching. Gas phase filtration is reacting. Gases move by diffusion, from high to low concentration, and removing them requires adsorption—getting molecules out of the air and onto the surface of materials like activated carbon, alumina, or zeolites. Unlike particle filters, gas phase filters don't fill up. They run out. They lose effectiveness over time, and there's no pressure gauge to tell you when. Surface Area Is Everything: Most activated carbons have around 1100 square meters per gram of surface area. That's not the exterior of the pellet. That's the interior pore structure. Volatile organic compounds get inside, condense back into liquid form, and stay there. The physics of adsorption depend on molecular weight, concentration, residence time, and contact efficiency. You need the air to touch the adsorbent before it exits the filter. One Filter Won't Do It All: You can't use one type of gas phase media to remove everything. Basic activated carbon handles many organic compounds. Acid gases like sulfur dioxide require chemically treated carbon. Ammonia requires another type entirely. Think of it like particulate filtration: pre filter, intermediate filter, final filter. Same logic applies to chemicals. The Four Global Markets: Corrosion control accounts for 60 to 65 percent of the global gas phase filtration market, driven by electronics manufacturing, data centers, and industrial facilities where chemical contamination voids equipment warranties. Wastewater odor control is second. Indoor air quality in commercial buildings is third. Airborne molecular contamination in semiconductor manufacturing is fourth. The total global market is approximately $2 billion and growing at 5.5 percent annually. GUEST: Christopher Mueller Global Director, High Purity Segment, AAF International https://www.linkedin.com/in/chrismullerconsulting/ AAF International https://www.aafintl.com/ The Air Quality Matters Podcast in Partnership with Particles Plus https://particlesplus.com/ Eurovent (https://www.eurovent.eu/) - Aico (https://www.aico.co.uk/) - Lindab (https://www.lindab.ie/) The One Take Podcast in Partnership with SafeTraces (https://www.safetraces.com/) and Inbiot (https://www.inbiot.es/?utm_campaign=simon&utm_source=airqualitymatters&utm_medium=podcast) - Farmwood (https://farmwood.co.uk/) Do check them out in the links and on the Air Quality Matters Website. (https://www.airqualitymatters.net/podcast) If you haven't checked out the YouTube channel its here (https://www.youtube.com/@airqualitymatters-SimonJones). Do subscribe if you can, lots more content is coming soon. Chapters 00:00:00 Introduction: Meeting the Gas Phase Air Cleaning Guru 00:02:51 The Fundamental Difference: Particulate vs Gas Phase Filtration 00:09:29 The Science of Adsorption: How Gas Phase Filters Actually Work 00:17:10 The Swiss Cheese Approach: Multi-Stage Gas Phase Filtration 00:23:20 Form Factors and Physical Products: From Pleats to Packed Beds 00:28:00 Precision and Specificity: Can You Target Individual Chemicals? 00:34:20 The Four Markets: Where Gas Phase Filtration Is Applied Today 00:38:24 Corrosion Control: The Hidden Giant of Gas Phase Filtration 00:44:00 Indoor Air Quality and the IAQP Opportunity 00:48:38 The Commercial Reality: Why Gas Phase Is Still a Hard Sell 01:13:49 Materials and Sustainability: What Is Activated Carbon Made From? 01:24:13 The Path Forward: Education, Standards, and Market Evolution 01:36:35 Closing Thoughts: Making the Invisible Visible
NOW PLAYING
Beyond Particulates: How Gas Phase Filtration Protects Everything From Data Centers to Lungs 117
No transcript for this episode yet
Similar Episodes
No similar episodes found.