Sch 3 para 21
As regards cases of any specified class, being a class such that the variety in the circumstances of particular cases within it calls for the making of special provision for particular cases, any of the following purposes, namely— (a) conferring on employers or other persons power to make rules or give directions with respect to matters affecting health or safety; (b) requiring employers or other persons to make rules with respect to any such matters; (c) empowering specified persons to require employers or other persons either to make rules with respect to any such matters or to modify any such rules previously made by virtue of this paragraph; and (d) making admissible in evidence without further proof, in such circumstances and subject to such conditions as may be specified, documents which purport to be copies of rules or rules of any specified class made under this paragraph.