Maintenance requirements for GMDSS equipment for vessels operating in Sea Areas A1 and A2 - SOLAS - Ch IV - 15 - an insight In order to ensure the maintenance requirements specified in SOLAS Reg. IV/15, one of the following measures should be taken as may be approved by the flag administrations: Duplication of equipment; Shore-based maintenance; or At sea electronic maintenance capability Please consult with the flag administrations for details or contact us for more information on the same.