Section 30(3)(b) in Bihar Inland Vessels Rules, 2013
(b)be able to give a clear explanation of the principles on which oil, gas or other internal combustion of the principles on which oil, gas or other internal combustion engine works, including the methods of ignition, to point out the difference between them and to show by means of illustrative sketches and otherwise, that he understands the details of the constructions of those in general use.