Portable Appliance Testing (commonly known as PAT or PAT Inspection or PAT Testing) is a process that routinely tests electrical appliances/items by a qualified engineer. Designed to protect employees as well as tenants. It is recommended that all portable appliances must be certified as electrically safe, ideally once a year. So that includes any electrical items that can be plugged into the mains, like kettles, lamps, microwaves, and TVs.