A Japanese Fire Prevention Ordinance 'No Open Flame' sign. Typically posted with two additional signs at the entrances of venues where such behavior is prohibited by law, such as department stores, theatres, underground malls, buildings over 100 metres tall, etc. This is the old design, which was replaced in 1 April 2020.
Drawn according to diagrams published in Japanese Fire Prevention Ordinances.

Article 25 of the Fukushima City Fire Prevention Ordinance (Archived)
Japanese government.
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