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phc November 2021 www.phcppros.com
Air Cleaners Debate
While ASHRAE and ventilation professionals struggled to be heard by international bodies, manufacturers responded to worldwide demand for indoor air quality solutions "guaranteed to prevent indoor airborne transmission of the virus." Of course, making such a guarantee is discouraged by ASHRAE because it cannot yet be fully established by the evidence. Studies have been taking place, but it is all very new, and science takes time to reach anything close to conclusive recommendations. As noted previously, ASHRAE's first statement on air cleaners was conservative: "Only use air cleaners for which evidence of effectiveness and safety is clear." Most commentators suggest that some air cleaners are probably helpful if people are willing to pay for them, but first steps should be adequate fresh air ventilation, humidity control, and HEPA or MERV 13 filtration. Numerous "virus-killing" products have been introduced, many of which have been purchased by schools and institutions using government funds. Critics question claims and comment on established proven methods and priorities. Ionization and ultraviolet light air filters are targets due to a perceived paucity of research verifying that they work. Ultraviolet lights in water systems seem to be well accepted, but in air systems, there are questions about effectiveness. In May, the International Ultraviolet Association signed a Memorandum of Understanding with ASHRAE to work together on research and tests around UV-C devices of all kinds, with the hope that a set of standards can be created. Ionization technology makers should probably try for something similar, but it appears they have not done so yet. Criticism has ranged from calling the technology a scam to just saying it is still unproven. Rheem and some other major players introduced ionization products and my own research suggests there are likely conditions in which they work well. According to Christian Avedon at Airius Fans, its new PureAir unit kills the SARS-CoV-2 virus. When I challenged him on it, he sent me a study from the Bulgarian Academy of Science, which conducted tests with the product. It would be wrong of me to suggest that this one study is conclusive because I'm not a scientist. But to an untrained eye, the methodology seems to have been carefully developed and worth reading. Dr. Ivanka Nikolova writes at the end of the document: "Based on the research, it can be scientifically concluded that the air and surfaces purification system - after 60 minutes of operation in a room achieves a reduction of viral saturation from HCoV OC43 - respectively from SARS-Cov-2 with not less than 98.4 percent." I will leave it to the HVAC professional community to draw its own conclusions. If anyone would like me to send the PDF, please email me at bfnagy1@gmail.com.
ASHRAE'S Most Recent Pronouncement
On Jan. 21, the ASHRAE task force issued a more detailed guidance document titled "In-Room Air Cleaner Guidance for Reducing COVID-19 in Air in Your Space/Room." It repeated much of the foregoing, but included this statement about UV-C used in air systems and ionization: "These technologies are designated by CDC as emerging technologies without an established body of evidence reflecting proven efficacy under as- used conditions." ASHRAE's task force (https://bit.ly/3mcO0eP) continues to issue COVID-19-related guidance documents in 2021, including: "Guidance for Small Temporary Dining Structures," "Laboratory One Page Guidance," "Practical Guidance for Vaccine Refrigerated Transportation and Storage Abstract," and "Ventilation for Industrial Settings During the COVID- 19 Pandemic." A recent Harvard Business Review article cites a 2015 study by Nicholas Bloom and coauthors that found work at home policies increased productivity by 13 percent to 22 percent. "Companies can save on real estate costs, hire and [use] talent globally, mitigate immigration issues and experience productivity gains, while workers can enjoy geographic flexibility," the report says. This suggests that for some companies and some employees, there are good reasons for continued working-from-home policies. Smart building professionals will be ready to help people make the work transition from office to home, with sensible advice, knowledge and understanding of their challenges and motivations. Those who do will likely be rewarded. O BF Nagy is becoming a renowned climate solutions specialist, author of the critically acclaimed book "The Clean Energy Age," and more than 200 articles on clean energy, clean water technologies, green government programs and energy economics. A podcast host and broadcast personality, he has traveled all over North America interviewing experts in climate science, government, engineering, architecture, clean transport, renewables and storage. Nagy also is a consultant to governments, corporations, trade organizations and research bodies.
THE FUTURE IS NOW
PureAir ionization fans are installed in a craft brewery in New Jersey.
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