Taxis asked to ventilate using air conditioner

NHK -- Nov 27

Japan's transport ministry has asked taxi drivers to use the fresh air mode of their vehicles' air conditioners to reduce the risk of coronavirus infection. It also requested that they wear masks and ask passengers to do the same.

The ministry sent the requests through a taxi industry group after studying simulations by the supercomputer Fugaku at the RIKEN research institute.

The computer examined the effectiveness of air conditioners in ventilating taxis. The simulation assumed that a taxi was carrying two passengers in the rear with a partition between them and the driver.

The analysis showed that when the windows were closed and the air conditioner was put into fresh air mode, the air in the taxi was replaced with air from outside in about 90 seconds.

It took about half that time, or around 45 seconds, when fresh air mode was maximized.

The computer also showed that the amount of droplets dispersed through a cough by a mask-wearing passenger was some 30 percent of that of a passenger without a mask.

A ministry official said taxi drivers should use the air conditioner to ventilate when they have to keep the windows closed due to the cold weather.