- Counting your Sea Service Experience
Sea service is a measurement of a mariners experience. It is counted in eight-hour calendar days from age 16 and accumulates over a person’s lifetime. This experience is not “used up”, “burned” or otherwise consumed when a credential is issued. Keeping track of your experience is the mariner’s responsibility, not the Coast Guards.
One day of sea service experience means that you were on a boat while it was away from the dock for four hours or more and held a position of responsibility. Examples of positions of responsibility include handling lines, cleaning the deck, watching out for other vessel traffic or steering the boat. For the purpose of sea service one month means 30-days and one year of means 360-days.
Inland Verses Ocean Sea Service Experience
Sea service experience is counted as either inland or ocean, depending on were the vessel was operated in relation to the COLREGS demarcation line. COLREGS stands for Collision Avoidance Regulations (Rules of the Road) and the demarcation line, or boundary line, is the dividing line between where the Inland Rules and International Rules apply. In general it is a line drawn between the most seaward points of land at the entrances to harbors, rivers and bays (it is marked on NOAA charts). If the entire day was spent shoreward of the boundary line than that day counts as an Inland sea day; but if the boat was operated seaward the boundary line then that day may be counted as an ocean sea day.
The exception to this is the Strait of Juan De Fuca, Puget Sound, the inside passage and Southeast Alaska. In these areas the International Rules apply, but experience counts as Inland sea time. It does not count as ocean time unless you are west of Angeles Point in the Straits or west of the islands in SE Alaska.
For the purpose of sea service experience vessel size is measured as Gross Registered Tons (GRT). This is not a measurement of a vessel’s weight, but of the volume of space in the hull. Every 100 cubic feet of hull space is equal to one GRT. For documented vessels the GRT is listed on the certificate of documentation for the vessel; for state registered vessels the GRT can be estimated using this formula: (depth x width x length) ÷ 100 = GRT.