58.—(1) Each owner and each occupier shall, to the extent consistent with the rights and obligations arising out of their respective interests in a protected structure or a proposed protected structure, ensure that the structure, or any element of it which contributes to its special architectural, historical, archaeological, artistic, cultural, scientific, social or technical interest, is not endangered.

(2) The duty imposed by subsection (1) in relation to a proposed protected structure arises at the time the owner or occupier is notified, under section 55 or under Part II, of the proposal to add the structure to the record of protected structures.

(3) Neither of the following shall be considered to be a breach of the duty imposed on each owner and each occupier under this section—

(a) development in respect of which permission under section 34 has been granted;

(b) development consisting only of works of a type which, in a declaration issued under section 57(3) to that owner or occupier, a planning authority has declared would not materially affect the character of the protected structure or any element, referred to in subsection (1) of this section, of that structure.

(4) Any person who, without lawful authority, causes damage to a protected structure or a proposed protected structure shall be guilty of an offence.

(5) Without prejudice to any other defence that may be available, it shall be a good defence in any proceedings for an offence under subsection (4) to prove that the damage to the structure resulted from works which were—

(a) urgently required in order to secure the preservation of the structure or any part of it,

(b) undertaken in good faith solely for the purpose of temporarily safeguarding the structure, and

(c) unlikely to permanently alter the structure or any element of it referred to in subsection (1).