2.—(1) Subject to sub-paragraph (2), the cleaning of the windows of any building (whether inside or outside) and the cleaning of the interior of any building fall within Article 4(1)(b).
(2) The following do not fall within Article 4(1)(b)—
(a)the cleaning of the exterior (which here excludes windows) of any building;
(b)the cleaning of the administrative headquarters of any district council.