Roofs and roof coverings shall be classified, installed and used in accordance with nationally recognized good practice as follows:
(a) Class A roof coverings are those which are effective against severe fire exposures and possess no flying brand hazard.
(b) Class B roof coverings are those which are effective against moderate fire exposures and possess no flying brand hazard.
(c) Class C roof coverings are those which are effective against light fire exposures and possess no flying brand hazard.
(Ord. 64-55. Passed 8-18-64. )