(a) At all MARSEC Levels, the owner or operator of a cruise ship must ensure the following:
(1) Screen all persons, baggage, and personal effects for dangerous substances and devices;
(2) Check the identification of all persons seeking to board the vessel; this check includes confirming the reason for boarding by examining joining instructions, passenger tickets, boarding passes, government identification or visitor badges, or work orders;
(3) Perform security patrols; and
(4) Search selected areas prior to embarking passengers and prior to sailing.
(b) At MARSEC Level 3, the owner or operator of a cruise ship must ensure that security briefs to passengers about the specific threat are provided.