An sign for indicating a smoking area within a building that is a designated place by the Fire Prevention Ordinance (department stores, high rises, underground malls). It's required to be white with black text at least 10 centimetres (3.9 in) by 30 centimetres (12 in) in size, and an optional English message.
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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