Code

In IMO usage a Code is a structured instrument of technical or operational requirements that takes legal force through a parent convention rather than standing alone. The ISM Code is made mandatory by SOLAS Chapter IX, the ISPS Code by SOLAS Chapter XI-2, and the IMDG Code by SOLAS Chapter VII. A code may be mandatory or recommendatory, and a recommendatory code can be made mandatory by later amendment, as happened with the IMSBC and Polar Codes. Codes let the IMO update detailed technical rules under tacit acceptance without reopening the parent convention text.