Out of thin air: Filtration system could be a key in combatting COVID

Bill Tillman, left, and Paul K. Carlton Jr. discuss
the Killer Filter that could eliminate COVID-19
and other contaminates from the air.

“Whatever you do, don’t call it a COVID killer,” cautioned Bill Tillman, a Fredericksburg engineer who created a highly efficient, low-cost air filtration system that does just that.

Coming out of retirement to team up with his longtime friend, former Air Force Surgeon General Lt. Gen. (retired) Paul K. Carlton Jr., MD, Tillman has revived his company, Isolate, Inc., which produces air filtration systems that clean viruses and just about everything else out of indoor air.

Tillman doesn’t want his system to be called a COVID killer because it has not yet been scientifically tested against the virus. It has been proven to “kill all airborne mold and bacteria, including the hard-to-kill surrogate for weaponized anthrax,” Tillman said, noting the anthrax surrogate is “10 times harder to kill than any virus.”

The multi-prong approaches the men use to filter indoor air is also effective against allergens and other airborne contaminates.

Isolate was incorporated in 1994 and has been “involved with HEPA (High Efficiency Particulate Air) air filtration projects including clean rooms for semiconductor plants, pharmaceutical facilities, hospitals, medical clinics, and anywhere clean air is essential,” according to its website.

“The Isolate engineers developed in-room 100% HEPA exhaust air filtration units to create negative pressure isolation exam rooms for the Diagnostic Hospital (of Houston, now part of the Methodist Hospital System)” the website says.

When Carlton saw what Tillman was doing back then, he knew he was onto something big.

“We finally found somebody at the University of South Florida, who would test it against the surrogate for weaponized anthrax, and it killed it cold, period,” Carlton recalled.

Carlton, who was a professor at Texas A&M for 10 years, retired in 2012. Tillman retired and closed down his business in 2015. When the COVID-19 pandemic began shutting everything down in 2020, Carlton realized that Tillman’s product might hold the key to combating the disease.

“I called Bill and said, ‘Come out of retirement, we need to get this into major production.’ I then put together a briefing that I took to a variety of people that accepted it,” he said. “But the CDC (Centers for Disease Control and Prevention) said, ‘this is not airborne. This is a surface transmitted disease.’ And I never understood that until Dr. (Anthony) Fauci made one statement. And the statement was, ‘we will never say anything that we have not proven to be true at CDC.’ Well, that’s a recipe for disaster in war. You always have Plan A, Plan B, Plan C. No plan survives first contact with the enemy.”

 

An airborne enemy

After doing some research, Carlton concluded that COVID-19 is transmitted through air, in addition to touch. Knowing that the average person spends as much as 80% of their day indoors, it became apparent that the key to fighting COVID-19 could be through air filtration. Getting medical professionals to believe him, however, is difficult.

“The engineers said a long time ago, ‘it’s the air you guys,’ but the medics didn’t agree. And unfortunately, the medics won,” Carlton said. “And so this blinded us and the COVID experts, because we continue to believe as a medical community with Dr. Fauci, that it’s not airborne, it’s droplets, which then drop out within six feet, and it’s surface.”

Lessons from the past

Carlton looked back at studies from the Spanish flu pandemic of 1918-1919. He said 40% of patients treated indoors died compared to 13% of those placed outside in tents. Fresh air and sunshine made a difference.

That’s where Tillman’s air filtration system comes into play. Designed as portable room-sized units, he can also modify it to accommodate a building’s air conditioning unit, which is what he has done with his own Fredericksburg home.

“So, when Bill decided to retire and come here with his bride, then he designed his house so that when you walk in that house, you literally could build electric components, you could mix pharmaceuticals, you can build all the circuit boards you wanted to. Just like a cleanroom,” Carlton said.

Tillman offered a tour of the unit in his attic and showed a measuring device that indicated there were zero particulates being detected in his living room.

How it works

His UVC/HEPA “Killer Filter” system works backward from most standard air filtration systems. It brings dirty air in from the bottom and exposes it to ultraviolet light, which kills most microorganisms. The air then goes inside a cylindrical HEPA filter encased in aluminum coated wing fiber mesh.

“The dirty air comes in at the floor, which is where the all the particulate is going to fall,” Tillman said. “It’s sucked up in here. As it’s coming in. We’re killing it before it ever hits the inside surface. But when it hits the inside surface, it can’t go anywhere. This is a 99.97% filter. So we now have contained it and we’ve killed it. This one-two step is probably all we need. But there’s new technologies that have come up with.”

He said bipolar needlepoint ionization from a device in the unit pushed into the air stream causes particulates to have positive or negative charges and clump together, where they fall to the floor.

“It could be important with some aerosols,” he said.

Utilizing parts he still has warehoused in Houston and reopening his parts supply chains, Tillman has Isolate back in business. His units have been used effectively in a hospital in the Texas Panhandle as well as a school system in Puerto Rico, where the client said there have been no cases of COVID-19 since the units were installed.

He said the unit essentially creates a negative pressure isolation chamber in an ordinary room without throwing away heated or cooled air, which drives up electric bills. His unit recycles the air, taking in dirty air and returning it clean.

Carlton said the system isn’t 100% effective at eliminating microorganisms and other microscopic particles, which makes air exchanges an important component. He said studies are still under way, but it appears that about 10-12 exchanges (complete change of air in a room) per hour is what is needed. The men said their hypothesis about air exchanges is being borne out by competitors and others who are working on the problem.

Layers of protection

Carlton said air filtration alone won’t solve the COVID problem but said that the more layers of protection added increases the level of protection.

“I am not anti-vaccine. I am not anti-mask. I’m saying we haven’t used all the tools,” he said.

He said the vaccine will not prevent a person from getting COVID-19, but it will significantly improve their chances of survival and lessen their symptoms. He said masks have about a 60% effective rate at blocking the virus, which is why he recommends people use as many of the defenses as they can.

Although Carlton and Tillman are friends and have been collaborating on the project, they maintain a degree of ethical separation.

“So, there no financial involvement. Bill and I have kept separate financially, because I go and talk to government people all the time. And that I can’t do if I’m financially involved. So, I have no financial involvement,” Carlton said.

Locally, Tillman said his system is used by West End Pizza to help keep its staff and customers safe.

To learn more, visit www.isolate.com or call 713-937-9393.

(This story ran in the Nov. 3, 2021, edition of the Fredericksburg Standard-Radio Post.)