Smokers will need to give a second thought to lighting up a cigarette in public places in Seoul because a puff of cigarette could cost them 100,000 won ($89.19) in fines. 

Starting yesterday, Seoul’s three landmark plazas - Seoul, Cheonggye and Gwanghwamun - officially became nonsmoking zones to prevent secondhand smoke in crowded areas.

The measure is based on a revised ordinance that - in addition to public plazas - also designated public parks, bus stations, school zones and gas stations as nonsmoking areas beginning yesterday. 

The revised ordinance was passed by the Seoul Metropolitan Council last November.

To minimize confusion, the Seoul Metropolitan Government will start a public campaign to raise awareness of the three nonsmoking plazas. 

The campaign will last until May 31, World No Smoking Day, and people caught smoking in the plazas beginning June 1 will be fined up to 100,000 won, the Seoul Metropolitan Government said. 

Twenty-three public parks, including Namsan and Yongsan, managed by the city government and 295 bus stations along central lanes will be smoke-free from September and December, respectively. 

The city plans to expand nonsmoking areas gradually. 

By Kim Mi-ju [mijukim@joongang.co.kr]