The International Maritime Organization (IMO) is an organization under the United Nations, and it is responsible for global shipping regulations. Maritime Safety Committee, MSC, is the highest technical body of IMO.
There are two key IMO documents that are relevant to water mist systems on ships:
SOLAS, the International Convention for the Safety of Life at Sea. SOLAS is a maritime treaty that sets the minimum safety requirements for merchant ships.
FFS Code, International Code for Fire Safety Systems. The FFS Code is a set of treaties under SOLAS, and it contains the requirements for the installation, performance and component testing for fire protections systems on board ships.