The pastors of an Arizona megachurch that is holding an event featuring President Trump on Tuesday is claiming the church's air filtration system can kill "99.9% of COVID within 10 minutes." Dream City Church Senior Pastor Luke Barnett and Chief Operations Officer Brendon Zastro make the erroneous claims in a promo video that has been circulating online this week. The video has been removed from the church's Facebook page.
"We have exciting information about what we're doing to fight COVID-19 here at Dream City Church," Barnett says in the video. Zastro then says the church has installed a system from Clean Air EXP, a Phoenix-based company that uses technology developed by members of the church.
"We've installed these units and it kills 99.9% of COVID within 10 minutes," Zastro says.
"When you come into our auditorium, 99% of COVID is gone, killed, if it was even there in the first place," Barnett says. "Thank God for good technology."
The "technology," however, may be too good to be true. According to Clean Air EXP, the system can eliminate 99.9% of airborne coronavirus test surrogates from Coronavirus 229E and Cystovirus Phi6 – not COVID-19, specifically.
Jeffrey Siegel, a professor at the Department of Civil and Mineral Engineering, University of Toronto, said he's read the lab reports that the Clean Air EXP results are based on and they do not reflect how the filtration system would work in a real building.
"My problem with those results – from what I can tell, because it's not well described in the test report – they did it in an entirely sealed chamber, and that's just not a fair test," Siegel told CBS News on Tuesday.
He added that an air cleaner could be tested in a sealed box in a lab and might seem effective, but when you move it to a building, it could be ineffective. "You can't just go from laboratory test results and go, 'This is going to work in a building,' because the building is fundamentally different."
Siegel said this is the case for testing any air cleaner, not just this particular device. "When you take results from a sealed chamber test, you have essentially entirely stacked the deck in the favor of the device, but it's not realistic, it's not going to translate to a real building," he said.
Aside from the unrealistic testing that was done for this filtration system, Siegle said, "there's no filter or air cleaner in the world that could reduce risk in a crowded, indoor environment."
"Filtration or air cleaning is not a good way of protecting people who are close to each other, because fundamentally, you have to get the droplets that contain the virus to the air cleaner and remove them before they are inhaled or land on someone else and eventually end up in their respiratory system."
Siegel said filtration has a role, but it's "not a silver bullet, magic approach."
While air purifiers may help reduce some airborne contaminants, including viruses in a home or confined space, neither a portable air cleaner or HVAC system is enough to protect people from COVID-19, according to the EPA. "When used along with other best practices recommended by the Centers for Disease Control and Prevention, operating an air cleaner can be part of a plan to protect yourself and your family," the EPA says.
The CDC also recommends hand washing, avoiding touch your face and wearing a mask in public to help slow the spread of coronavirus.
In a statement to CBS News, Dream City Church said the post about the filtration system was meant to inform the congregation "we are doing everything we can to foster the cleanest, safest environment as we resume church services."
"We have heard coronavirus and COVID used interchangeably. Our statement regarding the CleanAir EXP units used the word COVID when we should have said coronavirus or COVID surrogates," the statement continues. "We hope to alleviate any confusion we may have caused."
The church said they have been directing questions regarding the filtration system to Clean Air EXP and it is the church's understanding "that they tested with a third-party Certified Biosafety Laboratory on the best coronavirus surrogates available."
"The company found that their technology leads to a 99.9% elimination of airborne coronavirus surrogates," Dream City Church's statement reads. "So while they do not eliminate COVID-19, their coronavirus surrogate testing results are significant for the future of clean air."
The church said in the statement they are proud to be a customer of Clean Air EXP.
Fauci advised staying away from large crowds. "The best way to protect yourself and to prevent acquisition of and spread of infection is to avoid crowds. Avoid crowds. If in fact, for one reason or other, you feel compelled to do that, which we don't recommend, then wear a mask at all times," Fauci told Portnoy.
Ahead of the Tulsa rally, a combination of volunteers and staff from local health authorities (including the Tulsa County Health Department) handed out blue surgical masks to attendees and conducted no-contact forehead temperature checks under sterile-looking white tents.
Similar safety measures will be in place for Tuesday's rally in Phoenix. All attendees will have their temperature checked at the door and there will be hand sanitizing stations throughout the church, city officials were told, CBS affiliate KPHO reports.
While the City of Phoenix made has face masks mandatory in public places, Phoenix Mayor Kate Gallego said this rule won't be enforced at the Trump event, according to KPHO.
"We are not going to do enforcement during the rally, but we will hope that Governor Ducey, who is there, will tell people to wear masks. He believes in masks. He's a great spokesperson, but the best spokesman would be the president. If he told people at the rally, I bet they would do it," Gallego said, according to KPHO.
There are 58,179 confirmed coronavirus cases in Arizona, according to the state's health department. Mr. Trump is expected to speak in front of 3,000 people at the rally at Dream City Church.
CBS News has reached out to Clean Air EXP for comment and is awaiting response.