After receiving the notice required by section 238, the certifying officer may, if he thinks fit, cause the ship to be surveyed at the expense of the master or owner by a surveyor, who shall report to him whether the ship is, in his opinion, seaworthy and properly equipped, fitted and ventilated for the service on which she is to be employed:
     ¹[Provided that he shall not cause a ship holding a valid certificate referred to in sub-clause (i) or sub-clause (ii) or sub-clause (iii) of clause (c) of section 242 to be surveyed unless, by reason of the ship having met with damage or having undergone alterations, or on other reasonable grounds, he considers it likely that she may be found unseaworthy or not properly equipped, fitted or ventilated for the service on which she is to be employed.]