Metro passengers in Seoul are required to have their face masks on during rush hour, as of Wednesday, to prevent the spread of the novel coronavirus, Seoul city government said.

Passengers without face masks are banned on subways when the proportion of passengers to train capacity surpasses 150 percent, according to Seoul metropolitan government.

Announcements will be made when the ratio reaches 150 percent to notify passengers to put on their masks, while train staff restrict mask-less passengers from entering trains.

Passengers can purchase dental masks at 448 vending machines at subway stations as well as 118 stores and 157 convenience stores.

When the proportion exceeds 170 percent, trains are directed to omit stops at crowded stations, the Seoul city government said.

Seoul metropolitan government plans to dispatch staff at the 10 most packed stations and 10 transfer stations to make sure passengers keep a safe distance from one another, starting next month.

To reduce congestion, Seoul city has also increased the number of trains in operation during commuting hours, it added.

Subway operator, Seoul Metro is offering a service that provides forecasts on sections expected to be the most crammed the next day on top of time slots and passengers to train capacity ratios for subway lines one to eight via social media, official website and mobile applications.

By Kim Bo-gyung (lisakim425@heraldcorp.com)