The following sections of the CLC Part II state:
Specific duties of employer
...(c) investigate, record and report in the manner and to the authorities as prescribed all accidents, occupational diseases and other hazardous occurrences known to the employer
...(z.11) provide to the policy committee, if any, and to the work place committee or the health and safety representative, a copy of any report on hazards in the work place, including an assessment of those hazards;
Duties of committee
...(e) shall participate in all of the inquiries, investigations, studies and inspections pertaining to the health and safety of employees, including any consultations that may be necessary with persons who are professionally or technically qualified to advise the committee on those matters;
The following sections of the COHSR state:
15.4 (1) Where an employer becomes aware of an accident, occupational disease or other hazardous occurrence affecting any of his employees in the course of employment, the employer shall, without delay,
(a) appoint a qualified person to carry out an investigation of the hazardous occurrence;
(b) notify the work place committee or the health and safety representative of the hazardous occurrence and of the name of the person appointed to investigate it; and
(c) take necessary measures to prevent a recurrence of the hazardous occurrence.
(2) Where the hazardous occurrence referred to in subsection (1) is an accident involving a motor vehicle on a public road that is investigated by a police authority, the investigation referred to in paragraph (1)(a) shall be carried out by obtaining from the appropriate police authority a copy of its report respecting the accident.
(3) As soon as possible after receipt of the report referred to in subsection (2), the employer shall provide a copy thereof to the work place committee or the health and safety representative.
A - As you can see, the employer must advise the WPHSC immediately and request that the WPHSC participate in the inquiries.