What is tacit acceptance, and what does it apply to?

flowchart LR
  A["Amendment proposed and circulated at least six months ahead"] --> B["Adopted by a two-thirds majority in the expanded MSC"]
  B --> C{"What is amended?"}
  C -->|Articles or Chapter I| D["Explicit acceptance by two-thirds of Contracting Governments"]
  C -->|Technical chapters of the Annex| E["Deemed accepted after two years unless more than one-third, or fleets of 50% of world tonnage, object"]
  E --> F["In force six months later"]

• What: the deemed-accepted-unless-objected procedure of SOLAS Article VIII and MARPOL Article 16 that keeps the technical rules current; silence counts as acceptance.
• Procedure: circulated at least six months before consideration; adopted by a two-thirds majority of Contracting Governments present and voting in the expanded MSC, at least one third present.
• Technical Annex: deemed accepted at the end of two years from communication unless more than one-third of Contracting Governments, or Governments with fleets of not less than 50% of world gross tonnage, object; in force normally six months later.
• Not covered: amendments to the Articles or to Chapter I need explicit acceptance by two-thirds; a whole new Convention needs ratification.
• Why: fire-safety rules, equipment carriage and the Annex VI measures enter into force on a predictable timetable without fresh national ratifications.
• India: bound unless it objects; DGMA gives effect through the M.S. Rules under the Merchant Shipping Act 2025.