Regulation 20—Explosives manager's certificate of competency (1) A manager shall ensure that in relation to explosives for which that manager is responsible(a) each activity which involves the explosives is carried out under the supervision of an Explosives Manager who has a certificate of competency;(b) a person does not carry out, or at the request of another person carry out, the duties of an Explosives Manager, unless that person or that other person proves to the satisfaction of the Chief Inspector that that person or that other person(i) is the holder of a recognised degree or diploma in mining or an equivalent qualification and in addition has complied with the examination requirements;(ii) has at least four years practical industrial experience;(iii) has worked as a blastman for at least two years;(iv) is the holder of a certificate of competency to conduct blasting operations issued by the Chief Inspector;(v) has satisfied a board of examiners appointed by the Commission of that person's or other person's knowledge of explosives and these Regulations;(vi) has a certificate from a qualified medical practitioner stating that that person or that other person has sound sight and hearing and is not subject to any bodily or mental infirmity likely to interfere with the efficient discharge of that person's or that other person's duties; and(vii) is the holder of a recognised first aid certificate.(2) At least one of the members of the board of examiners appointed under subparagraph (v) of paragraph (b) of subregulation (1) shall be a senior mine officer.(3) A certificate of competency shall be for a period of not more than five years and may be renewed for a further period of five years if the holder is exercising duties as an Explosives Manager.