We recommend Tarnish-Me-Not to be reapplied every three months to jewelry that is worn regularly. For occasionally worn pieces, it is recommended to reapply the coating every six months. The time duration before suggested reapplication varies by how often the jewelry is exposed to certain wear-and-tear factors; such as: water, humidity, sweat, skin oils, cosmetic products and UV rays. Customers that are more susceptible to skin allergies are advised to reapply the coating more often; one to three months for regularly worn items, and every four to six months for occasionally used items. While other customers, less susceptible to skin allergies, have reported spraying their jewelry only once every 12 months.