An employer must ensure that an employee is under medical surveillance if-
(a) the employee may be exposed to an HCA listed in Table 4 of Annexure 2;
(b) the exposure of the employee to any chemical agent hazardous to his or her health is such that an identifiable disease or adverse effect to his or her health may be related to the exposure, there is a reasonable likelihood that the disease or effect may occur under the particular conditions of his or her work, and there are techniques to diagnose indications of the disease or the effect as far as is reasonably practicable; or
(c) the occupational health practitioner recommends that the relevant employee should be under medical surveillance, in which case the employer may call on an occupational medicine practitioner to ratify the appropriateness of such recommendation.