Section 4(2) in The Merchant Shipping (Tonnage Measurement Of Ships) Rules, 1960
(2)No deduction on account of any space shall be made under sub-rule (1) unless--(a)the space has been certified by a surveyor as reasonable in extent and properly and efficiently constructed for the purpose for which it is intended;(b)a notice is permanently marked in or over such space stating the purpose for which it is to be applied.
