Respirators — special kinds of facemasks — offer protection against harmful PM2.5 particles when venturing outdoors, and are highly recommended for people living in China. In fact, they’re essential for people who ride their bike or scooter to work or spent a lot of time on the streets of Shanghai. We suggest wearing one when the Air Quality Index (AQI) is higher than 200. But even at 151 it's wise to take note — at this AQI reading, the US Consulate considers it unsafe for prolonged outdoor activity.
Choosing a Mask
When choosing a mask, there are plenty of factors to keep in mind before making your purchase. So while you’ll have no problem finding facemasks in convenience stores across China, those masks might not always be the best choice.
The most important thing to pay attention to when buying a facemask is how it fits against your face. Gaps or air leaks render the mask worthless, so you’ll want a mask that’s snug and airtight.
Another thing to keep in mind is that the best brands follow American standards. Essentially, the mask models will be numbered according to the amount of particles they filter out of your lungs and higher numbers mean better ratings. So an N95 mask, for example, would be one of the most effective options as it filters out 95 percent of airborne particulates. A handful of foreign brands offer N95 models, including 3M, Totobobo and Vogmask. The latter two also offer children’s sizes.
You’ll also want masks that are comfortable and provide good ventilation. Look out for those that have an exhalation valve, which will make breathing easier.
It's also important to note that indoor air can be just as bad, or worse as outdoor air. Indoor air is 10-3o times more polluted than outdoor air so it's also just as important to take additional measures for indoor spaces too.