National Marker Company sign with legend ?CAUTION - EAR PROTECTION MUST BE WORN WHEN ENTERING THIS AREA? is commonly used at construction sites or industrial facilities to mark areas where high decibel noise can damage hearing. It has the legend printed in bold and legible text to ensure better readability. The caution sign complies with OSHA standard and displays the message in yellow text on black base with black text on yellow base. The material is UV resistant, chemical resistant, graffiti proof and has NMC Sign Muscle coating that protects the text against fading, scratches, scuffing, mold, and moisture.