Thank you for not smoking.

Visited my grandmother in a hospital. I saw her for the first time since I started to work.

Spotted this sign at the car park of the hospital. I had never seen a sign that says "Thank you for not doing" until then. As far as this sign is concerned, however, such an indirect phrasing does not seem to agree with the directness one may get from the Japanese sentence: the Japanese one is strictly saying that smoking is prohibited at all the premises.