30.—(1) Anything done by a person in the course of his employment shall be treated for the purposes of these Regulations as done by the employer as well as by the person.
(2) Anything done by a person as agent for another shall be treated for the purposes of these Regulations as done by the principal as well as by the agent.
(3) It is immaterial for the purposes of this regulation whether an employer or principal knows about or approves of an act.
(4) In proceedings under these Regulations against an employer in respect of an act alleged to have been done by his employee it shall be a defence for the employer to prove that he took such steps as were reasonably practicable to prevent the employee—
(a)from doing the act, or
(b)from doing acts of that kind in the course of his employment.
(5) Paragraphs (1) and (2) shall not apply in relation to an offence committed under regulation 10(5).