Article 7 Validity of noise certificate
Subject to paragraph (2) and article 17, a noise certificate issued under article 5 shall remain in force without limit of time.
A noise certificate issued under article 5 shall cease to be valid for the purposes of article 3:
if the aircraft or any part of it is modified in any way which affects the ability of the aircraft to comply with the noise standards required by this Order, except if such modification is done in a manner and with material of a type approved by the Governor for the purposes of this Part of this Order either generally or in relation to a class of aircraft or to a particular aircraft;
until the satisfactory completion of any inspection or test of the aircraft required by the Governor to be made for the purpose of ascertaining whether the aircraft continues to comply with the noise standards required by this Order.