What is Annex III of MARPOL 73/78 (Regulation for the Prevention of Pollution by Harmful substances carried by sea in packaged form) and regulations ?

Both SOLAS and MARPOL refer to the International Maritime Dangerous Goods (IMDG) Code, which was developed by IMO as a uniform international code for the transport of dangerous goods by sea.

APPLICATION: Apply to all ships carrying harmful substances in packaged form.
Annex III regulations:
  1.  Application
  2.  Packing
  3.  Marking & Labelling
  4.  Documentation
  5.  Stowage
  6.  Quantity Limitations
  7.  Exceptions
  8.  Port state control on operational requirements.
  9.  Marine pollutant.
DEFINITIONS

New Ship:  A ship for which the building contract is placed or the keel of which is laid or which is at a similar state of construction on or after 27 sept, 2003.

Harmful Substances: are those substances which are identified as marine pollutants in the IMDG Code.

Existing ship: mans a ship which is built before 27 sept, 2003.