There are now a lot of face masks out there, both medical and non-medical. For guidance on non-medical masks, please see the following link to the instructions from Ontario Public Health:
Reusable face masks made of cotton, polyester, lycra, etc. suffice the requirements for face coverings in public places (put in place by local health agencies) – they are washable and therefore very economical.
However, to attain the same level of protection as a hospital setting, masks labelled "medical", "procedural", and "surgical" masks are rated in a 3 tier system as outlined below.
There are masks that look identical to a medical masks, but are NOT rated. Make sure you are reading the labels of the masks you buy, and that you buy them from a reputable supplier such as Levac Supply Ltd.