Says so right here. https://www.edmonton.ca/programs_services/emergency_preparedness/masks.aspx Scroll down to face coverings. Your source says it was based upon findings from the Ontario Human Rights Commission. So it has no real legal standing.

I would challenge, as Ive said before on here, that masks are cosmetic face diapers with no real virus prevention effectiveness and therefore can not be held applicable to health & safety regulations. Anyone showing symptoms should be isolating anyways so the masks are simply virtue signalling and mass imposition of globalist values over our personal freedoms. Take your slave mask, made by slaves, off and breathe in some freedom.