1907 Hague Convention X

“Hospital ships were covered under the Hague Convention X of 1907.[8] Article four of the Hague Convention X outlined the restrictions for a hospital ship:

  • Ship must be clearly marked and lighted as a hospital ship
  • The ship should give medical assistance to wounded personnel of all nationalities
  • The ship must not be used for any military purpose
  • The ship must not interfere with or hamper enemy combatant vessels
  • Belligerents, as designated by the Hague Convention, can search any hospital ship to investigate violations of the above restrictions
  • Belligerents will establish the location of a hospital ship”

http://avalon.law.yale.edu/20th_century/hague10.asp