In the era of the emerging virus, plastic barriers have become widespread everywhere in the world, especially in restaurants and offices, which prompts the question of their effectiveness.

While these “shields” have become one of the most prominent social distancing measures, scientists blew up a shocking surprise. The New York Times quoted them as saying that plastic barriers that are supposed to protect against germs and viruses do not help reduce the spread of Corona infection and give people a false sense of safety.

Under normal conditions in stores, classrooms, and offices, small airborne particles are dispersed by air currents. Depending on the ventilation system, they are replaced with fresh air approximately every 15-30 minutes.

But building plastic barriers can alter the airflow mechanism in a room, disrupting normal ventilation and creating “dead zones”, where particles can build up in certain areas and become highly concentrated.

Increased risk of infection
A study published in June led by researchers from Johns Hopkins University in the United States showed that office barriers in the classroom are associated with an increased risk of infection with corona.

Researchers in the Massachusetts School District also found that glass partitions in the side walls of the main office obstruct airflow. A study looking at schools in Georgia also concluded that office barriers had little effect on the spread of corona compared to improvements in ventilation.

unintended consequences
In addition, Catherine Knox, professor of environmental engineering for buildings at the University of Leeds, said that erecting barriers seems like a good idea, but it can have unintended consequences. She added, “The effect is to prevent larger particles, but smaller air particles move over the barriers and mix in the room air within approximately 5 minutes,” noting that “this means that if people interact for more than a few minutes, they are likely to be exposed to the virus regardless. about barriers.

“I think having a large number of barriers can be a problem especially in places like classrooms where people are there for longer periods of time,” she said, stressing that this “obstructs airflow and creates higher risks that are difficult to identify.”

Very specific positions
For their part, the researchers say that plastic or glass barriers are likely to help in very specific situations and people are partially protected from transmission, for example the bus driver is protected from the rest of the passengers by a barrier extending from floor to ceiling, and the cashier at the bank who sits behind a wall of glass .

It is noteworthy that before the epidemic, a study published in 2014 reported that office divisions were among the factors that may have contributed to the transmission of tuberculosis in Australia.