While the ship is at sea, there must be available at all times a supply of electrical energy sufficient to operate the radio installations and to charge any batteries used as part of a reserve source of energy.

Both the VHF and MF/HF installations must be simultaneously supplied.

A means of ensuring a continuous supply of electrical power must be provided to all GMDSS equipment that could be affected by an interruption in power.

If a UPS or equivalent is used to supply power to the ship's GPS receiver or other source of position International Regulations for Preventing Collisions at Sea, 1972 – COLREG al information, a means must be provided to ensure the continuous supply of the information in the event of a failure to the ship's main or emergency source of power.

Information contained in a distress alert includes the name and position of the distressed vessel, and may include additional information such as the nature of the situation and what kind of assistance that may be required.