‘Don’t take the elevator at the same time as others and wear a mouth mask’ – Science

When you book a hotel again, you better consider asking for a room on a lower floor.

According to a Chinese study, taking the elevator appears to increase your risk of being infected with the corona virus. After all, the virus particles remain in the air for 20 minutes. Is this correct?

Where does this news come from?

Chinese researchers investigated how a person infected with the corona virus can infect the environment. The scientists used the data of one person for this: Mrs. A0.

• On March 19, 2020, A0 returned from the United States symptom-free but infected with the coronavirus. As a result, she had to be quarantined alone in her apartment.

• Mrs. B1 lived in an apartment under A0, and never had direct contact with A0. B1 and A0, however, used the same lift, but never together.

• On March 26, B1 received a family visit who stayed overnight in her apartment. We call this visit B2.

• On March 29, B2 went to a party at C1.

• On April 2, C1 was urgently admitted to a hospital for a brain haemorrhage, but also infected 28 other people with the coronavirus. In total, A0 indirectly infected more than 71 people in two hospitals with the corona virus.

The researchers conclude that one infected person can infect an entire population in a short time, and that the transfer from A0 to B1 could only have happened via the elevator, since neither person had any contact.

In a second study, researchers examined how many viruses were present in an elevator.

• In a well-ventilated elevator, 78% of the emitted particles remained suspended in the air by an infected person.

• In a poorly ventilated elevator, 99% of the emitted particles remained in the air.

A third study used a spray to find out how long virus particles lingered in an elevator. It usually took 12 to 18 minutes for the number of so-called aerosol particles to decrease by a factor of 100. With permanently open elevator doors, this time was reduced to 2 to 4 minutes.

How should we interpret this news?

There are many reasons not to take a lift. Climbing stairs, for example, is healthier. These limited studies suggest that an elevator as a closed space is not without risk in corona times.

• The first study suggests that the infection happened via the elevator, but cannot prove it. The contamination of B1 by A0 can also have happened in other places.

• The second study is actually the report of a research project, not a checked study. In order to become infected via an elevator, the circumstances must be challenging: standing in the elevator with or right after an infected person who coughs, not wearing a mouth mask, …

• In the third study, which evaluated aerosols in elevators with a spray, the researchers indicate that mechanical ventilation in hospital elevators can easily be increased through the control system to reduce aerosols.

The American Centre for Disease Control recommends that in elevators:

• wear a mouth mask;

• if possible not to talk;

• limit the number of people;

• wash your hands afterwards.

These measures actually apply to all closed and / or poorly ventilated areas. It is not known how many people actually became infected with the corona virus via elevators.