Art. 96 - Measurement of Deck Spaces:

For vessels fitted with superstructures, the following rules, which concern only such spaces as are excluded from the national tonnage, are applied.

A - Vessels with one tier of superstructures only :

(1) Poop, bridge, forecastle :

The following exemptions are allowed under certain conditions :

• Such length of the poop measured from the in side of the stern timber, at half height of the said poop, as shall be equal to 1/10th of the full length of the ship.
  
• The Portion of the bridge in way of the light and air spaces of the engine and boiler spaces, is being understood that such light and air spaces are not considered to extend beyond the forward bulkhead of the stoke-hold and the after bulkhead of the main engine-room.
  
• Such length of the forecastle measured from the inside of the stem at half height of the said forecastle, as shall be equal to 1/8th of the full length of the ship.
  
• In each of the above three cases of superstructures, such portions as are in way of corresponding openings in the sides of the ship, not provided with any means of closing.

(2) Poop and bridge combined, or forecastle and bridge combined :

In each of these combined spaces, the following exemptions are allowed under certain conditions :

• a) That length only which corresponds to the openings of the engine-room and boiler spaces as specified in (1b) above.
  
• b) Such portions as are in way of corresponding openings not provided with any means of closing in the sides of the ship.
  

(3) Shelter-decks.

In the case of shelter-decks. the following exemptions are allowed under certain conditions:

• a) The portions in way of corresponding openings in the side plating of the ship not provided with any means of closing.
  
• b) Such air spaces as are situated within the shelter-decks must be measured into the engine-room space and deducted together with 75% of their volume.

B - Vessels having more than one tier of superstructures :

1. The exemptions Prescribed in paragraph A-(I), (2) and (3) above are applicable in their entirety to the lowest tier only.
   
2. Tiers above the lowest tier. are only allowed the exemption of such portions as are in way of corresponding openings in the side plating of the vessel not provided with any means of closing.