§69.123. Figures. — Inbound Citations

(2) If the tonnage deck is stepped, the line of the tonnage deck is the longitudinal line of the underside of the lowest portion of that deck parallel with the upper portions of that deck. Steps that do not extend from side to side or are less than three feet in length are ignored when establishing the line of the tonnage deck. (See § 69.123, figures 1 and 2.) Spaces between the line of the tonnage deck and the higher portions of that deck are not included in under-deck tonnage.

(1) Measure the length of each structure along its centerline at mid-height to the line of the normal frames. (See § 69.123, figure 11.)

(5) An interior or exterior opening that is temporarily closed by cover plates or boards held in place only by hook bolts (see § 69.123, Figure 12) is considered open to the weather—

(i) If hook bolts used to secure cover plates or boards are spaced at least one foot apart and hook over a stiffener installed around the perimeter of the opening;

(ii) If the cover plates or boards fit tightly against the weather side of the bulkhead; and

(iii) If battening, caulking, or gaskets of any material are not used.

(i) The crown is the top of the main space of the engine room to which the heights of the main space are taken. The crown is either the underside of a deck or, if the side bulkheads are sloping, the uppermost point at which the slope terminates. (See § 69.123, figures 13 and 14.)