Made using premium "Power Grade" photoluminescent materials, glow safety shower signs work by absorbing light during the day and using it to glow at night. Not only do these signs comply with DIN 67510-1, ISO 15370, IMO Resolution A.752(18), and PSPA Class B, but also exceed the ASTM standards. Easy to spot in a black-out, the glow safety shower signs are great for emergency procedures.