CA Harb & Nav Code § 658.3 (2021)
2021 California Code|Harbors and Navigation Code - HNC|DIVISION 3 - VESSELS|CHAPTER 5 - Operation and Equipment of Vessels|ARTICLE 1 - Operation and Equipment|Section 658.3.

658.3.  (a) A person shall not operate a motorboat, sailboat, or vessel, unless every person who is on board and who is under 13 years of age is wearing a United States Coast Guard-approved wearable personal flotation device that is used in accordance with approval labels and manufacturer’s instructions while that motorboat, sailboat, or vessel is underway.(b) Subdivision (a) does not apply to a person operating a sailboat on which a person who is under 13 years of age is restrained by a harness tethered to the vessel, or to a person operating a vessel on which a person who is under 13 years of age is in an enclosed cabin.(c) A person on board a personal watercraft or a person being towed behind a vessel on water skis, an aquaplane, or similar device, except for an underwater maneuvering device intended for use by a submerged swimmer, shall wear a United States Coast Guard-approved wearable personal flotation device that is used in accordance with approval labels and manufacturer’s instructions. An underwater maneuvering device is a towed or self-powered apparatus that a person can pilot through diving, turning, and surfacing maneuvers that is designed for underwater use.(1) This subdivision does not apply to a person aboard a personal watercraft or a person being towed behind a vessel on water skis, if that person is a performer engaged in a professional exhibition, or preparing to participate or participating with authorization pursuant to a United States Coast Guard permit or other permit granted pursuant to subdivision (a) of Section 268 in an official regatta, marine parade, tournament, or exhibition.(2) In lieu of wearing a United States Coast Guard-approved wearable personal flotation device as described in this subdivision, a person engaged in slalom skiing on a marked course or a person engaged in barefoot, jump, or trick waterskiing may elect to wear a wetsuit designed for the activity and labeled by the manufacturer as a water ski wetsuit. A United States Coast Guard-approved personal flotation device as described in this subdivision shall be carried in the tow vessel for each skier electing to wear a water ski wetsuit pursuant to this paragraph.(d) The requirements set forth in subdivisions (a) and (c) do not apply to a person 13 years of age or older operating a motorboat, sailboat, or vessel if the vessel is engaged in an emergency rescue situation.(e) Subdivision (a) does not apply to a person operating a “passenger vessel,” as defined in Section 2101(22) of Title 46 of the United States Code or a “small passenger vessel,” as defined in Section 2101(35) of Title 46 of the United States Code.(f) The following definitions govern the construction of this section:(1) “Enclosed cabin” means a space on board a vessel that is surrounded by bulkheads or canvas, and covered by a roof.(2) “Operate a motorboat, sailboat, or vessel” means to be in control or in charge of a motorboat, sailboat, or vessel while it is underway.(3) “Underway” means all times except when the motorboat, sailboat, or vessel is anchored, moored, or aground.(g) A violation of this section is an infraction punishable as provided in subdivision (a) of Section 668.(Amended by Stats. 2015, Ch. 75, Sec. 1. (AB 638) Effective January 1, 2016.)