The South Korean government has updated its recommendations for when pollution is bad enough to wear a face mask.<br />In the guidelines released today, it says healthy people can go out without a mask even on days when pollution is considered bad that is, when fine dust concentrations are up to 50 micrograms per cubic meter.<br />But for the elderly, pregnant women and people with certain health conditions, masks are recommended when fine dust is higher than 36 micrograms.<br />At home, the government advises opening the windows at least three times a day for 10 minutes, even when the air is bad.<br />As for light exercise outdoors, it's recommended when dust is under 75 micrograms, but in or near a park rather than on the roadside.<br />
