It’s Section 5-5 of the OHS Regulation, which provides: 
First aid personnel
5‑5(1) An employer or contractor shall:
(a) provide the personnel set out in Table 9 of the Appendix for:
(i) the level of risk associated with the work carried out at the place of
employment as determined by a workplace first aid risk assessment; and
(ii) the number of workers at the place of employment at any one time;
and (b) ensure that the personnel are readily available during working hours.
(2) An employer or contractor shall ensure that the personnel required pursuant to subsection (1) have the qualifications set out in Table 1 or Table 3 of the Appendix, as the case may require
https://www.canlii.org/en/sk/laws/regu/rrs-c-s-15.1-reg-10/latest/rrs-c-s-15.1-reg-10.pdf 
You need to scroll down to the Tables in the Appendix and apply the criteria to your own situation. Hope that helps.