Section 31(a) in The Merchant Shipping (Examination Of Engineers In The Merchant) Navy Rules, 1963
(a)in the case of a candidate for a Second Class Certificate, the service has been performed in lake or river steam vessels of not less than 66 nominal horse-power and/or motor vessels of not less than 373 brake horse-power, and the candidate has had, in addition to his lake or river service, at least three months' qualifying service at sea in a foreign-going ship of the equivalent service in the home-trade; or
