AMSA Safety Alert - Hydrostatic Release Units Loss Prevention Loss Prevention Published: December 01, 2021 Contact author Download article pdf AMSA have recently released a new Safety Alert with reminders about the correct installation, use and maintenance of Hydrostatic Release Units (HRU) for both float free life-rafts and EPIRBS. Members are encouraged to review the Safety Alert - Hydrostatic Release Units and share with ships staff to ensure correct installation, use and maintenance of HRU’s.