42.—(1) An authorised officer may do all or any of the following things:

(a) at all reasonable times enter upon any premises in which a designated industrial activity is carried on where he has reasonable cause to believe any person is employed in the premises,

(b) examine either alone or in the presence of any other person, as he thinks fit, with respect to matters under this Act, every person whom he finds in any premises upon which he is entitled under this section to enter and require the person to answer such questions as he may put touching such matters, and to sign a declaration of the truth of the answers to the questions,

(c) examine the methods used in the training and instruction of any person whom he finds employed in a designated industrial activity in any premises mentioned in paragraph (b) of this subsection and give advice in such training and instruction.

(2) No one shall be required by virtue of paragraph (b) of subsection (1) of this section to answer any question or to give any evidence tending to criminate himself.

(3) An authorised officer may, by notice in writing served on a person carrying on a designated industrial activity, require him to furnish to the officer, within a specified time and in a specified manner, specified particulars with respect to the persons or any specified person employed by him in any employment in the activity.