According to the Factories and Industrial Undertakings (Safety Officers and Safety Supervisors) Regulations,

• 1. Duties of Safety Officer

(1)     shall be to assist the proprietor of the industrial undertaking in promoting the safety and health of persons employed therein, including for that purpose-

(a) advising the proprietor as to measures to be taken in the interest of the safety and health of persons employed in the industrial undertaking and, with the approval of the proprietor, implementing such measures;
(b) inspecting the industrial undertaking, or directing any person employed as a safety supervisor therein to inspect the industrial undertaking for the purpose of determining whether or not there is any machinery, plant, equipment, appliance or process or any description of work carried on in the industrial undertaking which is of such a nature as to be liable to cause risk of bodily injury to any person employed in an industrial undertaking;
(c) reporting the findings of any inspection carried out under sub-paragraph (b) to the proprietor and recommending what measures, if any, ought to be taken as a result of that inspection;
(d) assisting in the supervision of any person employed as a safety supervisor in the industrial undertaking;
(e) advising the proprietor in the interest of the safety and health of persons employed in the industrial undertaking of any repairs or maintenance that ought to be carried out in respect of-

(i) any premises comprising the industrial undertaking;
(ii) any appliance, equipment, machinery or plant in use in the industrial undertaking;

(f) investigating and reporting to the proprietor, or causing to be investigated and reported to the proprietor, the circumstances of any accident, or dangerous occurrence in the industrial undertaking and making recommendations to the proprietor to prevent similar accidents or dangerous occurrences;
(g) investigating and reporting to the proprietor, or causing to be investigated and reported to the proprietor, the circumstances of the suffering of any bodily injury by any person employed in the industrial undertaking and making recommendations to the proprietor to prevent similar suffering of any bodily injury;
(h) investigating and reporting to the proprietor every fatal accident in the industrial undertaking and making recommendations to the proprietor to prevent similar fatal accidents;
(i) receiving, discussing and countersigning every report submitted to him under regulation 17(1)(b)(iv) by a person employed as a safety supervisor;
(j) on or before the last day in every month preparing and submitting to the proprietor a report as provided in paragraph (2); and
(k) advising the proprietor on the implementation of a safety management system in the industrial undertaking, including the duties listed below-

(i) to assist in establishing, revising and reviewing a safety and health policy of the industrial undertaking;
(ii) to assist in organizing a safety and health training programme;
(iii) to assist in devising in-house safety rules and regulations;
(iv) to assist in implementing safety and health plans, programmes, arrangements and measures;
(v) to assist in establishing a safety committee and implementing its recommendations;
(vi) to assist in job hazard analysis, evaluation of potential hazards and the identification of hazardous conditions and hazardous exposure; and
(vii) to assist in conducting safety promotion, health assurance and personal protection programmes.

(2) A report submitted under paragraph (1)(j) shall be in the approved form (Form 2A or 2B).

• 2. Duties of Safety Supervisor

(1)     (a) to assist any person employed as a safety officer in the industrial undertaking in carrying out the duties of a safety officer under these regulations;
(b) to assist the proprietor responsible for the industrial undertaking in promoting the safety and health of persons employed therein including for that purpose-

(i) advising the proprietor or any person employed as a safety officer in the industrial undertaking, as to the observance by any person of the standards for the safety or protection of persons employed in the industrial undertaking;
(ii) supervising the observance by any person of the standards for the safety or protection of persons employed in the industrial undertaking;
(iii) promoting the safe carrying on of work in the industrial undertaking; and
(iv) on or before the last day in every week, preparing and submitting, in the case where no person is employed as a safety officer in the industrial undertaking, to the proprietor, or in the case where a person is employed as a safety officer in the industrial undertaking, to the safety officer, a report as provided in paragraph (2).

(2) A report submitted under paragraph (1)(b)(iv) shall be in the approved form (Form 3A or 3B).

Details can be referred to http://www.legislation.gov.hk/chi/home.htm