VANCOUVER -- With Canadian health officials now recommending the use of face masks when physical distancing isn't possible, there can be some confusion about which types of masks are the most effective.

Last week, Canada's chief public health officer, Dr. Theresa Tam, said that face masks are now recommended for those who can't keep a two-metre physical distance from others. B.C.'s premier said on Wednesday he plans to follow that advice

"I'll certainly be wearing a mask if I can't physical distance and I encourage all other British Columbians to do the same thing," Premier John Horgan said. 

"I expect if you're hopping on a SkyTrain or catching a bus … you're going to see increasing numbers of people who are wearing masks and (personal protective equipment) as they move around our urban centres."

But are all masks created equally and will any mask protect others from the spread of COVID-19? Here's what Dr. Rhonda Low, a Vancouver-based family physician, had to say about them on CTV Morning Live Monday. 

Jason Pires: Canada's top doctor is now recommending wearing masks when distancing isn't possible. So how much does wearing a mask block the spread of germs?

Dr. Rhonda Low: The quality of the mask makes a real difference as well as how well it fits on a person or how the user actually wears it. The idea is you want a good quality, thick mask – not something that's just a little scarf across your face, those won't do. A cloth mask of good quality seals on both sides of your face, that actually is a good mask. 

And then how you wear it, in the sense that we don't want you to touch your mask all the time, pull it down over your nose, you don't want to touch it, rub your eyes, rub your nose. That defeats the purpose because then you're going to put germs on your hands too and then you're touching everything else.

Keri Adams: Let's talk about these droplets. How long do they stay in the air or on surfaces?

Low: This sounds absolutely disgusting, but somebody who has a really good, moist cough, when they cough out, they can cough out a quarter of a teaspoon of fluid, and that aerosolizes a lot of the virus particles into the air. 

Adams: There's a lot of different types of masks out there. Are there any that can spread droplets?

Low: You want to be a good citizen and you're trying to protect others because we know that at least 25 per cent of folks can have COVID, not have symptoms, but can spread the germs. By wearing a mask you're being a good citizen by protecting other people as well … the primary purpose is to protect others. 

So these particular (valve) masks that a lot of people might have in their homes because they've done renovation projects, the little valve in there actually helps you breathe out easier … but in effect, these masks can help spread germs because what they're doing now is helping exhale and if you're sick, you're forcibly exhaling droplets through that little valve more, at a smaller aperture, which means the droplets go out quicker and could go farther.

So you can actually put other people more at risk by wearing these particular masks with the ventilators in them and small vents in them. 

The above interview has been edited for lengthy and clarity. Watch the entire interview in the video above.