Adopted in 2004, the BWM Convention is known officially as the International Convention for the Control and Management of Ship’s Ballast Water and Sediments. Though it took many years to ratify, its introduction triggered the development of today’s range of treatment systems.
Since its ratification in September 2016, the BWM Convention has made ballast water treatment a major issue worldwide. Newbuilds will require type-approved treatment systems as of September 2017, while existing vessels will need to have them retrofitted by their first vessel renewal survey after that date. In essence, all vessels will have to install a treatment system within a period of around five years.
Because the BWM Convention was established when less was known about the control mechanisms needed in ballast water treatment, IMO type approval certificates have developed over time. Certificates issued after 2014 offer more detail about the operating limitations of a system, such as salinity, temperature and UV transmittance levels. Any certificate issued before this date should be examined critically, and the newest revision of a certificate should always be sought.
Today the BWM Convention is interpreted in a more-or-less uniform way by third-party testing bodies worldwide, who strive to ensure a high degree of transparency in all testing procedures.