For the purposes of this Act, a vessel is an unsafe vessel if the operation of the vessel may endanger any person because of—
(a) the condition or equipment of the vessel; or
(b) the manner in which cargo and equipment on the vessel is stowed or secured; or
(c) the nature of the cargo; or
(d) the overloading of the vessel with persons or cargo; or
(e) the number or qualifications of its crew; or
(f) the absence of marine safety equipment that is required under this Act or the regulations to be carried or installed on the vessel.