Reference

The signal word on a safety sign encodes how certain the harm is, not how bad it would be. This guide defines all four ANSI Z535 signal words with their exact panel colors, shows where OSHA's three sign classes leave a gap at WARNING, and gives a clear two-question test for assigning the right header to any hazard you find.

OSHA sets safety sign rules in two separate places, and the ANSI editions it incorporates run two to three revisions behind what vendors sell as current. This guide decodes the three sign classes at 1910.145(c), the specified colors, accident prevention tags, and the construction table at 1926.200, plus exit and aisle marking duties.