A vessel of the United States on a voyage from a port in the United States to a foreign port (except to a Canadian port), and a vessel of the United States of at least 75 gross tons as measured under
section 14502 of this title, or an alternate tonnage measured under
section 14302 of this title as prescribed by the Secretary under
section 14104 of this title on a voyage between a port of the United States on the Atlantic Ocean and Pacific Ocean, shall be provided with a medicine chest.