46 CFR 25.25-15: -15 Retroreflective material for personal flotation devices.

(a) Each life preserver, each marine buoyant device intended to be worn, and each buoyant vest carried on a vessel must have Type I retroreflective material that is approved under subpart 164.018 of this chapter.

(b) Each item required to have retroreflective material must have at least 200 sq. cm (31 sq. in.) of material attached to its front side, at least 200 sq. cm of material on its back side, and, if the item is reversible, at least 200 sq. cm of material on each of its reversible sides. The material attached on each side of the item must be divided equally between the upper quadrants of the side, and the material in each quadrant must be attached as closely as possible to the shoulder area of the item.