What do you understand by the terms Protocol, Amendments and Convention? Describe the procedure for amendments to the regulations?

A Convention (e.g. MARPOL 73/78, SOLAS, MLC) is a formal, legally binding international treaty concluded between States under international law (often developed at the IMO/ILO), setting out binding obligations and standards. It is adopted at a diplomatic conference or under an organization's assembly, and enters into force after a defined number/fraction of States (and/or tonnage) have deposited instruments of ratification. Once accepted, parties must implement it in their national law and enforce it.

A Protocol is a separate international instrument modifying, supplementing or implementing an existing convention. A protocol may be used to substantially amend a convention (a "amending protocol") - e.g. the 1978 Protocol to SOLAS 1974 and the MARPOL Protocol; a protocol normally requires its own ratification and may be in force even if the original convention is in force, defining transitional arrangements. A protocol is a treaty in its own right, binding those States that ratify it; it often changes the convention it amends (e.g. the 1978 SOLAS Protocol incorporated changes and entered into force itself).

Amendments: Amendments are changes/modifications to the text of a convention agreed by the contracting States through the governing body, in accordance with the convention's amendment procedure. They can be made (a) by resolution/diplomatic conference, or (b) by the "tacit acceptance" or "explicit acceptance" procedure. They modify the treaty's requirements (e.g. a revised regulation) and bind parties once in force.

Procedure for amendments (typical for IMO instruments, e.g. MARPOL, SOLAS):

• A proposed amendment is submitted to the relevant committee (MEPC - Marine Environment Protection Committee for MARPOL; MSC - Maritime Safety Committee for SOLAS) by a member State or through the secretariat.
• The committee considers and, if agreed, the amendment is adopted by resolution at a session; the amendment text is circulated.
• Adoption: Under the "tacit acceptance" procedure of MARPOL/SOLAS: once adopted by a majority (e.g. not less than two-thirds of the parties to the parent convention present and voting at the Committee), the amendment is deemed accepted unless within a specified period (e.g. 10 or 18/24 months - for MARPOL 10 months, and for SOLAS/other 12-24 months) a defined number/fraction of parties (e.g. more than one-third of the number of parties, parties whose merchant fleets constitute a proportion of tonnage) notify their objection. If the number of objections is below the threshold within the period, the amendment enters into force for all parties automatically at the set date.
• For instruments adopted by a diplomatic conference, the amendment is adopted by the conference and then goes through ratification; explicit acceptance requires each party to accept the amendment.
• The "tacit acceptance" makes amendments swift, as States are deemed to have accepted unless they object, so IMO can keep pace with technical/operational improvements (e.g. the sulphur cap, the IBC, the revised MARPOL annex).
• Once in force, parties implement the amendment in national law (through flag action) and enforce it; ships must comply on recognition of the revised requirements, and flag/port states enforce them; certificates are re-issued/records updated accordingly.