BLOOMBERG – Sales of plexiglass tripled to roughly $750 million in the U.S. after the pandemic hit, as offices, schools, restaurants and retail stores sought protection from the droplets that health authorities suspected were spreading the coronavirus.
There was just one hitch. Not a single study has shown that the clear plastic barriers actually control the virus, said Joseph Allen of the Harvard T.H. Chan School of Public Health.
“We spent a lot of time and money focused on hygiene theater,” said Allen, an indoor-air researcher. “The danger is that we didn’t deploy the resources to address the real threat, which was airborne transmission — both real dollars, but also time and attention.”
“The tide has turned,” he said. “The problem is, it took a year.”
For the first months of Covid-19, top health authorities pointed to larger droplets as the key transmission culprits, despite a chorus of protests from researchers like Allen.
Tinier floating droplets can also spread the virus, they warned, meaning plastic shields can’t stop them. Not until last month did the World Health Organization and U.S. Centers for Disease Control and Prevention fully affirm airborne transmission.
That meant plastic shielding had created “a false sense of security,” said building scientist Marwa Zaatari, a pandemic task force member of the American Society of Heating, Refrigerating and Air-Conditioning Engineers.
“Especially when we use it in offices or in schools specifically, plexiglass does not help,” Zaatari said. “If you have plexiglass, you’re still breathing the same shared air of another person.”
Recent CDC research found that desk or table barriers in Georgia elementary schools didn’t correlate with lower infection rates. Mask mandates and ventilation improvements did.
An April study published by the journal Science suggested that desk shields might even slightly raise the risk of Covid-like symptoms.
And a prepublication paper from Japan lacte last month linked plastic shielding with infections in a poorly ventilated office … Click here to read more.