Whenever you feel the need for a safety sign that is ANSI Z535-compliant, just use the Safety Sign Generator. Pick a level of warning with a signal word, select a pictogram or two, and write out any kind of notice you wish.
The examples here were generated by commenters at Metafilter. There are a ton of them if you need a laugh or some inspiration, although some are hilariously rude. Damon Burke, who designed the generator, also has one for Laboratory Door Safety Signs. Go wild with both of these!
TURN IT NO OTHER WAY
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