"Danger - Boiler Room, Authorized Personnel Only" Label by SmartSign | 5" x 7" 3M Reflective Laminated Vinyl 3M AUTHORIZED. Made from Certified 3M components: inks, laminate and films. 3M Engineer Grade reflective labels shine brilliantly at night. DURABLE VINYL. Conformable vinyl has 7 year outdoor life and aggressive adhesive backing. INSTALLATION. Labels stick to flat or curved surfaces and can be used indoors or outdoors. LAMINATED. UV-resistant, weatherproof overlaminate protects the label from moisture, solvents, chemicals, abrasion and fading. EASY TO CLEAN. Laminated vinyl labels can be easily wiped off to remove dirt, dust, or grease.