National Archives give the following information
Series details: BT 334
Board of Trade: Registrar General of Shipping and Seamen: Registers and Indexes of Births, Marriages and Deaths of Passengers and Seamen at Sea
1891-1972
The registers include both UK and foreign subjects, passengers and seamen. There is only one register for marriages.
The registers contain some entries related to the deaths of seamen ashore.
The death registers include entries for the SS Titanic and Lusitania.
