CHICAGO — CerroZone™ LLC’s air purification platforms have become the first to meet and exceed the requirements for Air Purifiers set out in the recently published ASHRAE Standard 241-2023 Control of Infectious Aerosols.

The same system previously earned 510(k) Class II clearance from the U.S. Food and Drug Administration as a recirculating air cleaner for eliminating airborne viruses and bacteria. FDA approval was contingent on extensive testing at accredited independent third-party facilities.

CerroZone’s mobile, mini, and in-ceiling/wall mount units are designed to purify air in buildings such as schools, retail environments, offices, and other indoor spaces. CerroZone’s indoor system achieved a 99.998 percent reduction of live COVID-19 Delta Variant in a single pass of approximately 1.2 seconds, according to independent testing at MRI Global in Kansas City.

CerroZone previously announced it had achieved Intertek’s Zero Ozone Certification. Intertek considers emissions of 0.005 ppm or less to be negligible per UL 2998, the North American industry standard for ozone testing. The CerroZone unit recorded at only 0.001 ppm, five times lower than the UL 2998 standard.

In this recent set of testing for compliance with Standard 241-2023, the CerroZone units demonstrated at each fan speed, efficacy against MS2 Bacteriophage, formaldehyde safety, and particulate matter (PM) count in a chamber larger than 800 ft3 at an independent, highly respected third-party laboratory – ARE Labs in Olathe, Kan.

Dr. Bill Bahnfleth (Fellow/Presidential Member ASHRAE, and a professor in the Department of Architectural Engineering at The Pennsylvania State University) and Dr. Max Sherman (retired Staff Senior Scientist from the Lawrence Berkeley National Laboratory with a research career spanning over 40 years and 200 publications) recently commented on ASHRAE Standard 241-2023: “Its requirements for filter and air cleaner testing go well beyond what is found in existing standards. They are a major step in the direction of creating uniform and effective technology-agnostic criteria for characterizing filter and air cleaner performance and safety that will support their effective application.”

CerroZone Director of Operations Marlon Robinson said, “We are now positioned to help building owners and engineers make their buildings ASHRAE 241-2023 compliant, safely.” CerroZone will publish its independent laboratory reports online on its website in the coming weeks, he noted.

Robinson continued, “We are also working on new tools for the industry including a small unit for elevators, large industrial units for grow houses as well as in-situ test results at various locations, and energy consumption versus additional ventilation, all verified by independent parties.” Announcements are expected in the near future, he said.

“We also welcome approaches by OEMs in this space who would like us to review the vast potential of integrating our technology into their platforms,” Robinson added. “CerroZone is ideally positioned to aid the public in the fight against emerging and future variants of infectious airborne diseases.”

Among its many benefits to the market, the CerroZone™ platform only requires annual preventive maintenance, unlike filtration-based systems that need quarterly replacement of filters and other components.

The patented CerroZone system was developed in conjunction with Micron Pure™, a Hecto Group™ company.

CerroZone is part of the Marmon Plumbing & Refrigeration group of Chicago-based Marmon Holdings, Inc. Marmon Holdings, a Berkshire Hathaway company, is a global industrial organization comprising 11 diverse business groups and more than 100 autonomous manufacturing and service businesses.

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