Section 4(1)(b) in The Merchant Shipping (Prevention of Pollution by Sewage from Ships) Rules, 2010
(b)a renewal survey shall be conducted at an interval not exceeding five years except where the provisions of sub-rules (2), (5), (6) and (7) of Rule 8 are applicable and the renewal survey shall be such as to ensure that the structure, equipment, systems, fittings, arrangements and materials fully comply with the requirements of these rules.