DETROIT – Now that face coverings are a requirement in Michigan, more people are interested in whether face shields might be a suitable alternative to masks.
Face coverings are widely accepted by the scientific community as one of the tools that decrease the transmission of the coronavirus (COVID-19). Unfortunately, some people have trouble tolerating masks.
Masks can be especially hot in the summer, and they block the mouth, limiting communication through facial expressions. In certain cases, face shields might be acceptable.
The primary purpose of a face covering is to decrease the amount of infected droplets and aerosols a person might cough, sneeze or breathe into the air, especially at close range.
Face shields are a simple plastic barrier that can be easily mass produced or even homemade They’re commonly used in hospital settings to protect health care workers from infected droplets, especially because they also shield the eyes.
But are they as effective as masks?
So far, no studies have been done to specifically compare the two in terms of COVID-19. But a 2014 study looked at how well face shields blocked flu droplets.
Researchers used a cough simulator and found that face shields reduced a person’s exposure to large cough droplets by 96%. Smaller droplets were able to flow around the shield and be inhaled, though.
The World Health Organization and scientists around the globe believe the coronavirus might linger in the air in the form of microscopic aerosols. Those particles are light enough that they would easily travel around a face shield in the air being breathed in and out, experts said.
While face shields would likely catch and stop large droplets from a cough or sneeze, there hasn’t been enough study of how well they can contain finer aerosols if the wearer coughs or sneezes.
The bottom line is that if a person can’t tolerate a mask or there is an important need to see someone’s facial expressions, face shields can be useful options. But at present, they aren’t being endorsed as a general alternative to face coverings by the Centers For Disease Control and Prevention or the Michigan Health Department.