When I was at Chouest they gave us sea time for every day worked. It did not matter that the boat was at the dock, underway or in dry dock.
USCG says “What counts as a “day”?
• A “day,” as defined by the regulations, is 8 hours of watch-standing or day-working, not to
include overtime.”
So on vessels over 100 tons all days worked count???
I had a conversation about that a few years back with the shoreside support staff regarding the crews sea time. Shoreside wanted to do a reduced amount of days because the vessel was at the dock quite a bit. Not out of service or out of the water. Those are the distinctions I found for when a vessel is out of service.
You are spot on with the definition of days and if you couple that with the CFR definition for not in service you see that even if the vessel is tied to the dock, but is crewed and ready to go, that is a sea day.
Addressing your question, I recommend looking at the following three documents and the wording provided e.g., service.
Crediting Sea Service FAQ
A day of sea service is any day that a mariner served upon a vessel in an assigned position in either the deck or engineering department of a vessel (not a passenger).
46 CFR 10.107 Definitions
Service (as used when computing the required service for endorsements) means the time period, in days, a person is assigned to work.
46 CFR 10.232 Sea Service
(a) Documenting sea service. e.g., Sea letter or discharges providing beginning date of service and end date of service.
(b) Service toward an oceans, near-coastal, or STCW endorsement will be credited as follows:
(1) Service on the Great Lakes will be credited on a day-for-day basis up to 100 percent of the total required service.
(2) Service on inland waters, other than Great Lakes, that are navigable waters of the United States, will be credited on a day-for-day basis for up to 50 percent of the total required service.
(3) Service on vessels to which STCW applies, whether inland or coastwise, will be credited on a day-for-day basis.
Interesting that days moored to the dock would count.
When I applied for my first license, based on my own recreational power and sailing vessels, a “day” had to be a minimum of four hours underway. Since I had to document 540 days, I provided copies of my carefully maintained logs.
When I requested a Transcript of Sea Service from the USN, they told me I would get underway credit for 60% of the time assigned to the vessel, unless I could document a greater percentage. I was able to do the latter.
Most companies write the seatime letters off the payroll records. They have no other way to do it. They sure as hell don’t have extra staff to paw through the logs submitted to the office to see how many hours the vessel was underway each day.
Certificates of Discharge are for the number of days onboard from signing on to signing off.
Recreational boating seatime is mostly very generous estimates of “ Seatime.”
Regardless of what the rules may say, these are the realities.
What counts as a “day”?
• A “day,” as defined by the regulations, is 8 hours of watch-standing or day-working, not to
include overtime.
• Only on vessels of less than 100 gross registered tons (GRT): Credit for a full day
will only be given for service of 4 hours or more (See 46 CFR 10.107, definition of “Day”).
No credit will ever be given for days in which less than 4 hours were served.
• For the purposes of defining sea service requirements, the Coast Guard considers 1 month
as 30 days, and 1 year as 12 months (or 360 days).
So your boat does not count unless it is over 100 tons and underway for 4 hours. I am very sorry Navy time does not count day for day
If you are working that 8 hour day and the vessel is in service you are on a sea day. The definition says 8 hours worked on the vessel. You work at the dock. And some boats, I.e. tugs etc, are on call out notice. So unless the boat is cold stacked or out of service……
Thank you for the elaborations.
I wasn’t complaining about any of the day crediting schemes, i.e. recreational, merchant or navy service. It all makes sense.
My first license required fuller documentation of the 540 days because it was an inspected license for auxiliary sailing vessels, inland, to 25 tons.
My Navy sea service was credited for my Deck license for the documented days underway (over eight hours). I was credited with 2,077 days, and sat for Chief Mate. My Navy time also included engineering assignments, and these were credited separately, and differently, than the deck service.
But on tug’s over 200grt subjected to stcw its day for days and not 1.5 days ?
From what I understand to get a 1.5 days you have to have it on your COI that you work 12 hour shifts.
No.
It just has to be on the seatime letter that you work 12 hour days (on a type of vessel where that is allowed).
I believe that the issue is developed into a watch standing issue. The COI and sea letters should represent the watchstanding arrangements on the vessel. See 46 U.S.C. 8104(g), 46 CFR 15.705,
Those vessel’s manning requirements authorized to operate a two-watch system six-on-six-off watch system with only two watch standing officers a 12-hour working day may in some cases be creditable as 1 1/2 days of service. 8 hour days normal represent a three-watch system.
Some industry sectors that may have USCG authorization for time-and-half credit e.g., crew boats, supply boats, towboats and some commercial fishing boats. Recommend having the sea letters reflect the vessel’s COI.
The NMC evaluates each case of the 12 hours worked but as was mentioned the wording of your sea time letter should include that you stand a 12 hour watch and that you participate in the companies random drug screening for at least the last six months. The form letters are pretty straightforward that I have seen over my career.
But sea time is an important issue since that is a large part of how we upgrade and improve our professional selves.
Pretty much any sailboat is at LEAST 12 hours a day and I would count it a miracle to not be woken up while off watch to attend to something at least once a day.
I never wrote up anyone for 1.5 days though, it never occurred to me. I guess there are some grey areas like if you anchor and start cleaning the boat, you are still “working”. Is making dinner working? 10-20-30 ton time is only worth so much anyway, so maybe no one digs into it that much.
I bring this up as if the boat is over 100 tons your sea service time counts as long as you are “on watch.” I think a lot of people thing the boat has to be underway for 4 hours to count as is the case on under 100 ton boats.
The “4 hours” only applies to vessels less than 100 tons so boats less than 100 GRT absolutely count. All vessels over 100 tons require at least 8 hours for a day of sea time.
I’m not sure what you mean, 4 hours ONLY counts as a day on vessels under 100 GRT.
As per NMC USCG
What counts as a “day”?
• A “day,” as defined by the regulations, is 8 hours of watch-standing or day-working, not to
include overtime.
• Only on vessels of less than 100 gross registered tons (GRT): Credit for a full day
will only be given for service of 4 hours or more (See 46 CFR 10.107, definition of “Day”).
No credit will ever be given for days in which less than 4 hours were served.
• For the purposes of defining sea service requirements, the Coast Guard considers 1 month
as 30 days, and 1 year as 12 months (or 360 days).
So if under 100 tons and underway for 4 hours it counts as a “day”
I bring up sea service as most yachts get it wrong. American’s get a full day of sea service for every day worked (boat must be over 100 tons) it does not matter if the boat stays at the dock. That is how the commercial world works.
“Worked” is a grey area for your own boat. My wife would probably sign off that my “sea service” is 24/7/365 
Maybe I need an “add a day” thing where for $20 you can scrub and clean my boat and I’ll sign the form, Tom Sawyer’s fence has nothing on me!