This specification covers the shape, size, spacing, and shading requirements of letters and numerals used in shipboard markings. Covered by this specification are five types of characters: plain letters and numerals (Type 1), block letters and numerals having the same width (Type 2), Type 2 characters with shading (Type 3), block letters and numerals of different widths (Type 4), and Type 4 characters with shading (Type 5). The characters shall be designed using the grid method, which will allow one to change the character size proportionately as required. Not covered in this specification are the location and size of various shipboard markings using letters and numerals.

1.1 This specification specifies shape, size, spacing, and shading of letters and numerals to be used aboard ship.

1.2 Characters are of Five Types:

1.2.1 Type 1—Plain letters and numerals (16 units).

1.2.2 Type 2—Block letters and numerals (12 units).

1.2.3 Type 3—Type 2 characters with shading (shading—1 unit).

1.2.4 Type 4—Block letters (10 units) and numerals (12 units).

1.2.5 Type 5—Type 4 characters with shading (shading—1 unit).

1.3 This specification does not give location or size of various shipboard markings incorporating letters and numerals.