The D643 Danger Confined Space Authorized Personnel Only sign complies with OSHA 29 CFR 1910.145. It's available in 2 sizes - 7"x10" and 10"x14". It's also available in 2 different materials - Sticker and Rigid Plastic.
All signs are coated with Sign Muscle. A proprietary coating that is graffiti proof and doesn't fade. Because of this, both materials are suited for indoor or outdoor use.