NMC OSHA signs are the perfect way to alert your employees and guests when a hazard is present in your facility. Header "DANGER" and legend "CONFINED SPACE HAZARDOUS ATMOSPHERE ENTER BY PERMIT ONLY". These OSHA signs comply with OSHA 29 CFR 1910.145. Rigid plastic 0.050 thick polystyrene material is ideal for long lasting indoor or outdoor use. Good chemical resistant. Maximum temperature: 183 degree F. Mounting: yes. Measures 7-inches length by 10-inches height.