The entire exhaust system, including exhaust hoods, grease filters, grease extractors, ducts, exhaust fans, pollution control devices, and other appurtenances, shall be inspected and cleaned at least once every 3 months by a person holding a certificate of fitness. Surfaces shall be cleaned to bare metal. The powder residue or other foreign substance left by saponifying agents or other cleaning materials shall be removed. Flammable cleaning fluids shall not be used. Cleaning fluids shall not be applied to fusible links or other detection devices of the fire extinguishing system.
- Commercial cooking equipment utilizing solid fuel shall be inspected monthly by a trained and knowledgeable person, and cleaned by a certificate of fitness holder as necessary but not less frequently than once every 3 months.
- Vertical portions of interior and exterior vertical ducts in excess of three stories in height shall be cleaned at least every 6 months by a person holding a certificate of fitness. Horizontal portions of such ducts, including all elbows, shall be inspected and cleaned in accordance with this section.