Ha Ha, what have you done wrong?? I see your in Southhampton 😉
They are very good and produce excellent freely published reports on all manner of Marine accidents. Its well worth having a look at their Accident reports, sadly many are very tragic, but the reports are always easy to read and make clear what lessons can be learnt. An interesting yet slightly morbid read!
Many of the pleasure craft ones tell the old story though – wear lifejackets, buy and learn to use VHF's, EPIRBS, Liferafts, dont drive speedboats pissed etc
The commercial investigations can be anything from Collisions and fires to accidents to members of the crew such as falls, crush injuries or drownings.