(a) Unicellular expanded polyvinyl chloride-acetate copolymer or synthetic rubber modified polyvinyl chloride, polymer or copolymer plastic foam shall be of three types as follows:
Type A—for life preservers, buoyant vests or buoyant cushions.
Type B—for buoyant vests or buoyant cushions.
Type C—for ring life buoys.
(b) [Reserved]