46 CFR §117.75

1. (a)Each life jacket carried on a vessel on an oceans, coastwise, or Great Lakes route, must have a life jacket light approved in accordance with Subpart 161.012 of this chapter. Each life jacket light must be securely attached to the front shoulder area of the life jacket.
2. (b)Notwithstanding the requirements of paragraph (a) of this section, life jacket lights are not required for life jackets on:
   1. (1)Ferries; and
   2. (2)Vessels with Certificates of Inspection endorsed only for routes that do not extend more than 20 miles from a harbor of safe refuge.