Cross-post: Open Letter to address the use of Electronic Air Cleaning Equipment in Buildings

Sarah - Good comments and I'm glad your heart is healthy! We need you around to keep up the good work. :-) I too had ionization in my house (by way of some portable HEPA filters) for years, but didn't really realize it until a year ago. Just one of those sneaky add-ins I didn't catch when we got those, but at least they can be turned off and it's still a good quality HEPA filter. Thinking on those comments, there seems to be relationship between what's effective, and what has potential negative health outcomes, which intuitively makes sense to me. An ion isn't smart enough to know the difference between a virus and healthy tissue, so I'm skeptical that concentrations that are low enough to not stress us are also effective at cleaning the air as proposed. Adding to my skepticism is that it seems like the manufacturer tests continue to appear to game the system - probably why these aren't submitted for peer review. The most recent batch of these "3rd party lab tests" I saw was immediately picked apart by researchers for several really compelling reasons. One, the researchers pointed out that the tests appeared to use orders of magnitude (like about 10-16x) greater a concentration of ions than what they are installing in the field. And second, even by bombarding the space with ions, if you mapped out the results compared to a HEPA filter rather than just natural decay, they would look terrible. But they don't present the results against filters, so the consumer isn't really evaluating apples-to-apples choices they have available. And that's important, because it leads to the "waste" part, especially when groups like schools with limited funds are putting it there instead of in addressing primary solutions like ventilation and filtration.   One of the letter supporters, Dr. Richard Corsi (Twitter: @CorsIAQ) has been critical of the way in which some electronic air cleaners run these tests, saying essentially that "I can easily design experiments to show that an old pair of socks removes 99% of viruses from air." Indeed, one guy appears to have taken that to heart, and in an entertaining example of how you can do this, he rebrands a good old banker's lamp and runs test showing that a "New Air Cleaner using Advanced ELGIT System Reduces Viruses, Mold and Bacteria by 93%." (Link: https://www.texairfilters.com/new-air-cleaner-using-advanced-elgit-system-reduces-viruses-mold-and-bacteria-by-93/) One final thought - and I'm trying to be cautious here, but feel it needs to be said to this group - but it's also become clear the last couple of weeks that there's clear effort to stifle the criticism of these devices. A quick search will show that a couple of the more vocal critics have already been slapped with defamation lawsuits by a manufacturer. And I've been told of threats against organizations some of us belong to, as well as the people who volunteer in those groups for articles or white papers that may echo the concerns laid out in the letter. Less litigious, but also frustrating are examples like the article we published about IAQ strategies in a fairly well-read magazine this month that was edited to run (without our permission) removing any criticism of these technologies. The editor stated that the companies are also advertisers, so they couldn't include the critique. Meanwhile, these companies are free to run their own pieces that go unchallenged in the same magazine.   Just to give some perspective on this, one sales rep shared with a colleague that they went from selling $1M a year in these devices pre-pandemic, to "$1M a month." Scale that out across all of the reps across the country, and that's going to create a heck of a legal fund that none of us really have the ability to take on individually. I guess what I'm saying is that I think that we would all be hearing a lot more about all of this, but those are some of the reasons why.