It's been shown by a few documentaries (by ARTE european channel) that up to at least the 3rd of march and in Beijing, you are not authorized to go out without a face mask (for grocery shopping for instance). Each family has a few "permits" available to go out but facemask (chirurgical type) is not an option for those going.

Your temperature as well as your mask compliance will be checked pretty much at every venue/transportation/shop.

Source (in french): https://www.youtube.com/watch?v=OQD_-2KI244