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Fort Worth Schools Spent Millions On Air Cleaners, But Do They Work?

Offers for air filtration systems such as bipolar ionization technology came pouring in after COVID-19, but the EPA and other experts have warned that the technology is largely unproven outside of lab conditions.

3D rendering of the deodorizing filter installed in the air purifier removes odors and harmful gases. Activated carbon usually adsorbs gaseous pollutants.
(TNS) — Fort Worth area schools have spent millions to buy an air cleaning technology officials hope will reduce the amount of coronavirus particles in the air, but experts say they aren't sure the technology actually works.

As evidence grew that the virus could spread via small particles and remain airborne for hours after a person emitted them through speaking or breathing, schools were pummeled with pitches to invest in technologies that could clean the air.

"We got no shortage of vendors, letting us know that they now have the perfect product to help with (COVID)," said Joseph Coburn, chief of the operations division for the Fort Worth school district.

And in many districts, the pitches worked. Of the electronic air cleaners sold to schools, one type has proven particularly popular. School districts throughout the United States have purchased and installed cleaners using bipolar ionization technology.

The Fort Worth school district approved a $2.7 million contract to buy bipolar ionizers to install in 79 elementary school campuses. The White Settlement school district approved a $781,000 contract to buy bipolar ionizers. Bipolar ionization units have also been installed in schools in the Birdville school district. Outside of Tarrant County, bipolar ionization units have been installed in the Mesquite school district and the Humble school district, north of Houston. Nationwide, an investigation from Kaiser Health News tallied more than 2,000 districts that had installed bipolar ionization units.

In theory, the technology works like this: the air cleaners add charged ions to the air, causing particles to stick together and inactivating viruses and bacteria.

But while the technology has proven popular in schools looking to keep teachers and kids safe and to keep classrooms open throughout the pandemic, multiple experts have said there is not enough rigorous scientific evidence to indicate the technology works as promised.

The federal Environmental Protection Agency warns that bipolar ionization "is an emerging technology, and little research is available that evaluates it outside of lab conditions."

Paula Olsiewski, a contributing scholar at the Johns Hopkins Center for Health Security, said she has not seen any studies that show ionization is effective in real world conditions.

Delphine Farmer, an atmospheric chemist at Colorado State University, said there is not a consensus among indoor building scientists or chemists about exactly what the devices do and how well they work.

Bipolar ionizers are "potentially adding things to the air," said Martin Cohen, assistant chair in the University of Washington Department of Environmental & Occupational Health Sciences. "We don't know as much health-wise as we could. We're not 100% sure that it's benign."

The use of bipolar ionization technology in schools highlights the difficult position that districts have been placed in without state or federal leadership to guide their decisions and separate fact from fiction, the experts said.


Before the 2020-21 school year began, the operations team at the Fort Worth school district began to review how it could keep schools open as the virus continued to spread.

The district's first step was to install high quality air filters in as many school buildings as possible, as recommended by multiple coronavirus experts as a useful tool to reduce the amount of virus in the air. Most experts have recommended using a filter with a minimum efficiency reporting value (better known as MERV) of 13 or higher to help reduce virus particles in schools and other indoor spaces with poor air flow. Before the pandemic, most schools used filters with MERV ratings of 8, which are slightly cheaper and require less energy to use.

The district installed these high-quality filters on many of its campuses. But the heating, ventilation and air conditioning systems in some buildings were incompatible with MERV 13 filters. Schools with rooftop air conditioning units were mostly incompatible with MERV 13 filters, said Stewart Brown, the district's director of environmental services.

For those schools, district officials looked for another solution.

In December 2020, the Fort Worth school board approved a $2.7 million contract to purchase bipolar ionization devices and install them on 79 elementary school campuses, according to materials presented to the board. The devices were furnished and installed by Trane, and were manufactured by Top Product Innovations and Global Plasma Solutions.

Fort Worth school board president Tobi Jackson declined to comment on the board's vote authorizing the purchase.

"This is a district operations decision which was brought to the board for approval," Jackson wrote in an email to the Star-Telegram. "I respectfully defer all questions to the superintendent and his designees as they are the experts in this arena."

A spokesperson for the school district referred questions to Coburn, the operations chief. Superintendent Kent Scribner did not respond to a message seeking comment.

A spokesperson for Trane said in an email she was not authorized to comment specifically on the project but said the company believes indoor air cleaning solutions have a place in HVAC systems.

"Every space is different and requires a tailored strategy for indoor environmental quality — it is important to get an expert assessment to determine which solutions are right for a space," the spokesperson wrote in an email.

She said the company supported standards and guidelines from the U.S. Centers for Disease Control and Prevention and other industry groups, and that Trane supported additional independent, third-party testing in the world of indoor air quality.

Top Production Innovations, which manufactured the devices, said in a statement that the company was "proud to support Fort Worth ISD with our Needlepoint Bipolar Ionization products, which play an important role in the district's multilayer strategy to make its comprehensive air cleaning and filtration systems even more effective."

Global Plasma Solutions, which developed the bipolar ionization technology, wrote in an email: "Hundreds of hours of controlled laboratory testing and results from thousands of high traffic, real world installations — including medical facilities, airports, universities and schools — have demonstrated that Needlepoint Bipolar Ionization is both effective and safe in helping to improve the quality of the indoor air as part of the layered solution to a complex problem. We will always agree that additional peer reviewed studies are needed across the entire indoor air quality industry, and we are proud to say we probably have conducted more rigorous scientific testing at accredited third-party labs than any other indoor air cleaning company and to have led the call for more robust testing standards to ensure greater public confidence in and understanding of this important technology."

Global Plasma Solutions is suing an air quality academic and an air cleaning company, accusing them of running a "smear campaign" against GPS. Global Plasma Solutions referred the Star-Telegram to Lyle Burgoon, a toxicologist with a doctorate in pharmacology and toxicology. Burgoon said GPS had retained him as an expert witness in its lawsuit. Burgoon criticized some of the peer reviewed research on bipolar ionization technology and said in his review of the literature, there had been adequate research on the safety and effectiveness of bipolar ionization units.


Bipolar ionization units work like you're charging a room full of air by plugging it into a wall socket, said Chris Cappa, the chair of the Department of Civil and Environmental Engineering at the University of California, Davis.

Global Plasma Solutions explains that its units release ions into the air, and that "when these ions disperse throughout a space, they seek out and form bonds with particles in the air," according to the company's website.

As more particles join, they form larger clusters. These clusters either become large enough that they drop out of the air, or the charge of the ions neutralizes the bacteria or virus in the particle clusters, according to the theory.

Seven experts interviewed by the Star-Telegram said they had two main questions about bipolar ionization: Does it actually work to clean the air in real world conditions? And is it safe to use?

The experts interviewed by the Star-Telegram agreed there was not enough research to answer each question confidently.

Both Farmer, of Colorado State, and Cohen, of the University of Washington, cited the precautionary principle as a guide in making decisions about introducing chemicals or technology into indoor spaces. The principle urges waiting until a specific intervention has been proven to be safe. So, in the case of bipolar ionization technology, indoor air quality experts said following the principle would mean waiting until research has conclusively shown that there are no adverse effects from the units before using them widely.

Burgoon, the toxicologist retained by Global Plasma Solutions, said in an interview he was "not a big fan of the precautionary principle."

"From my personal standpoint, the precautionary principle, although it does have its place, will also prevent us from having useful products on the market," Burgoon said.

All of the indoor air quality experts the Star-Telegram interviewed spoke generally about bipolar ionization technology, and did not comment on a specific manufacturer or device.


The questions that experts have about bipolar ionization technology are clear — if you know where to look.

"School systems should not use unproven technologies such as ozone generators, ionization, plasma, and air disinfection with chemical foggers and sprays," reads an April 2021 report from the Johns Hopkins Center for Health Security. "The effect of these cleaning methods on children has not been tested and may be detrimental to their health."

The American Society of Heating, Refrigerating and Air-Conditioning Engineers expressed caution in installing electronic air cleaners: "The data on the health consequences of electronic particle air cleaners are sparse," reads the organization's position statement on filtration and air cleaning.

Outside of the world of public schools, some industries have also begun to review the evidence behind bipolar ionization. Boeing tested two kinds of ionization technology and decided that neither worked well enough to install on its commercial planes, according to a report from the company. (The company tested only how well the technology works to destroy viruses on surfaces, and not whether it was effective at killing virus particles in the air.)

But amid a barrage of expert advice on everything from vaccine distribution, masking, physical distancing, student mental health, learning loss, and more, schools have found themselves overwhelmed in interpreting the best practices and recommendations on so many different topics from so many different groups.

Researchers who surveyed dozens of schools throughout the U.S. about their indoor air quality plans found school officials were frustrated by the many different guidelines that sometimes relayed conflicting messages, and often didn't include the technical advice that schools needed to improve ventilation and filtration with outdated air systems. In all, $190 billion has been made available to public and private schools during the pandemic.

"There's been so much funding available to schools to improve air quality, and very little clear guidance about what to do," said Farmer, the Colorado State chemist. "So this is in no way the fault of schools and superintendents who have to make decisions with very little information."

©2022 the Fort Worth Star-Telegram. Distributed by Tribune Content Agency, LLC.