Artikel 90

(1). The identification length1) When the tonnage length has been ascertained, the identification length will easily be found by adding to or deducting from the tonnage length, as the case may be, the length of the horizontal distances measured in the middle plane between the extreme points of the tonnage length and the points mentioned above (see Figure 117).is the length from the fore side of the uppermost end of the stem (see Figure 121) to the aft side of the uppermost end of the sternpost.
Should no sternpost exist, the length is taken to the point of intersection of the fore side of the rudder-stock (or its line of continuation) with the uppermost deck.
(2). The identification breadth is the extreme outside breadth which is ascertained in the same manner as indicated under Article 84 for the breadth under Rule II (see Figure 118).
Rubbing-pieces should not be included in this breadth.
(3). The identification depth is the vertical distance measured in the middle plane at half the identification length between the under side of the tonnage deck and the upper side of the double-bottom plating or floors. In ships having three decks or more, an additional identification depth shall be measured to the under side of the upper deck (see Figure 122).
When the identification depth falls in way of a recess or a projection in the double bottom, the depth should be measured to the bottom of the recess or to the top of the projection, as the case may be (see Figure 123).