Tobacco Hazards Prevention Act Article 21

The persons in charge of a place where smoking is prohibited or restricted, as well as the employees thereof, shall stop those who smoke in the non-smoking places pursuant to Articles 18 or 19, or those who are under the age of 20 to enter the smoking areas. Other on-site persons may dissuade those who smoke in non-smoking places or enter the smoking areas.
中文原文 菸害防制法第21條
於第十八條或第十九條禁止吸菸場所吸菸或未滿二十歲之人進入吸菸區,該場所負責人或從業人員應予勸阻;在場之其他人亦得予勸阻。

English translation for reference only; the Chinese text prevails. Not legal advice.