Usually by radio, but it may be signalled by any means. A message might read: "OFFER SALVAGE SERVICES BASIS LLOYD'S FORM LOF 2011 NO CURE NO PAY. MASTER (ASSISTING SHIP'S NAME) ".
Before arrival, either directly to the local authority or through an agent approved by the local authority, by radio, fax, email or other communications, so as to reach the local authority not more than twelve hours, and whenever practicable not less than four hours, before the expected arrival of the ship.
The Ship Security Officer (SSO) should advise the Port Facility Security Officer (PFSO) without delay. The PFSO should undertake an assessment of the situation in consultation with the SSO and agree on appropriate security measures with the ship, which may include completion and signing of a Declaration of Security. Any costs entailed in additional security measures would be settled by the ship.