Inspecting the premises where hazardous materials are located is common to all fire department permit applications. This may be a one-time inspection before a permit is issued, or regular recurring inspections may be required as a permit condition. This requirement usually pertains to restaurants, schools, theatres, clubs, and other businesses where flammable materials are used by the public or are being used where the public gathers. Other activities that usually need a permit are selling or operating fireworks and food trucks, installing and using liquified petroleum gas or oil-burning equipment, installing or removing underground fuel tanks, blasting, and events such as carnivals, fairs, exhibits, temporary structures like tents or canopies, and trade shows.