Coast Guard Documentation - BoatSign tips

from United States Coast Guard:

http://www.uscg.mil/hq/cg5/nvdc/nvdcfaq.asp
http://www.uscg.mil/hq/cg5/nvdc/nvdcfaq.asp#11

WHAT ARE THE VESSEL NAME AND HAILING PORT MARKING REQUIREMENTS?

Documented vessels do not display their official numbers on the outside of the hull, but are identified by the name and hailing port. The application for documentation must include a name for the vessel composed of letters of the Latin alphabet or Arabic or Roman numerals and may not exceed 33 characters. The name may not be identical, actually or phonetically, to any word or words used to solicit assistance at sea; may not contain or be phonetically identical to obscene, indecent, or profane language, or to racial or ethnic epithets. Once established, a vessel's name may not be changed without application, fees, and the consent of the Director, National Vessel Documentation Center. There is no rule against duplication of names for documented vessels, so hailing ports are helpful in identifying vessels.

HOW DO I MARK MY VESSEL?

The official number assigned to documented vessels, preceded by the abbreviation "NO." must be marked in block-type Arabic numerals at least three inches high on some clearly visible interior structural part of the hull. The number must be permanently affixed so that alteration, removal, or replacement would be obvious and cause some scarring or damage to the surrounding hull area.

The name and hailing port of a recreational vessel must be marked together on some clearly visible exterior part of the hull. The vessel name of a commercial vessel must also be marked on the port and starboard bow and the vessel name and the hailing port must also be marked on the stern. All markings may be made by any means and materials that result in durable markings and must be at least four inches in height, made in clearly legible letters of the Latin alphabet or Arabic or Roman numerals. The "hailing port" must include both a place and a State, Territory, or possession of in the United States. The state may be abbreviated.

Additional Boatsign Notes

Boats with Coast Guard documentation usually include the name of state in the hailport.  (In the case of Coast Guard Documentation, registration numbers are not used.)  See 1993 Coast Guard handout below...

MARKING OF NAME AND HAILING PORT

"For vessels documented exclusively for pleasure, the name and
 hailing port of the vessel must be marked together in clearly
 legible letters not less than four (4) inches in height on some
 clearly visible exterior part of the hull." (46 CFR ~67.15-3(a))
 Either the homeport or the hailing port may be marked on the boat;
 in either case, the abbreviation for the state must be shown.  
 Name and port may appear on any clearly visible part of the hull; 
 however, they must appear together.
 Any durable, legible method of marking is acceptable, including 
 script lettering.  Name boards are acceptable, if they are attached
 to the hull in a permanent manner.
For example - APPROVED     -- Vessel Name
             Essex, CT     -- Hailingport (town in which you 
                OR            live)
           New York, N.Y.  -- Homeport (nearest Coast Guard 
                              port where your papers will be
                              filed)

Usually, hailports utilize upper case letters, and no extra punctuation. For example, BoatSign.Com recommends  NY  instead of  N.Y. and  MA  instead of  Ma.

In my experience, some boat transoms may be too small to physically permit 4-inch hailport letters. In other cases, the transoms may present an outright ugly appearance if the hailport letters are made 4 inches in height.

If either case exists with your boat, then you (the boat owner) must make a decision about how you want your hailport presented.

My advice. Specify in your work order that your boat is documented, and that you want your hailport letters to comply with the regulations as well as possible. State also that you want the transom to be attractive and be presentable in a photograph.