This exemption is for people who want to work on a domestic commercial vessel being used for a wildlife or other sightseeing operation in inland waters.
Annex VI of the International Convention for the Prevention of Pollution from Ships (MARPOL Annex VI) allows ships to use exhaust gas cleaning systems (EGCS) to comply with the 0.50 per cent m/m sulphur fuel oil limit that commenced on 1 January 2020
When operating in the marine environment, there are compliance requirements you must meet. These include safety requirements, regular vessel surveys, permits and certificates of operation.