Authorized Personnel Only Signs

http://www.mysafetylabels.com/electrical-hazards-authorized-personnel-only-warning-label/sku-lb-2368

"Keep workers informed of the electrical hazards in your facility. Use this ANSI label to inform that only authorized personnel are permitted to enter."

http://www.mysafetylabels.com/electrical-hazards-authorized-personnel-bolt-symbol-label/sku-lb-2393

"Restrict unauthorized entry in the areas of electrical hazards by posting this label with a symbol of electrocution on it."