An undocumented vessel shall not be required to be numbered under this chapter if it is:
(a) Already covered by a number in full force and effect which has been issued to it pursuant to federal law or a federally approved numbering system of another state; provided, that such undocumented vessel shall be subject to the numbering requirements of this chapter if it has changed its state of principal use and has been within this state for a period in excess of 90 consecutive days.
(b) A vessel from a country other than the United States temporarily using the waters of this state.
(c) A public vessel of the United States, another state or subdivision thereof or municipality of such other state.
(d) A ship’s lifeboat.
(e) Any vessel belonging to a class of boats which has been exempted from numbering by the department after the department has found that the numbering of vessels of such class will not materially aid in their identification; and, if any agency of the federal government has a numbering system applicable to the class of vessels to which the vessel in question belongs, after the department has further found that the vessel would also be exempt from numbering if it were subject to the federal law. An undocumented vessel propelled solely by oars or paddles and an undocumented vessel eight feet or less propelled solely by sail are exempt from the provisions of this chapter.
(Amended by Stats. 1973, Ch. 759.)