27.—(1) A person authorised by the appropriate district council in relation to this paragraph may, at any reasonable time and having given at least 24 hours' notice to the occupier, and to the owner if known, enter a dwelling-house to which this Part applies for the purpose of survey or examination–
(a)where it appears to the council that survey or examination is necessary in order to determine whether any powers under this Part should be exercised in respect of the dwelling-house; or
(b)where a notice of unfitness or a notice of disrepair has been served in respect of the dwelling-house.
(2) A person authorised by the appropriate district council under Article 25(3) may, at any time and having given at least 6 days' notice of his intention to do so to the occupier, and to the owner if known, enter any dwelling-house for the purpose of doing any work required to be done in relation to the dwelling-house by a notice of unfitness or a notice of disrepair or, as the case may be, by such a notice as varied by the county court under Article 22(3).
(3) An authorisation for the purposes of this Article–
(a)shall be in writing stating the particular purpose or purposes for which the entry is authorised; and
(b)shall, if so required, be produced for inspection by the occupier or anyone acting on his behalf.