Many have always wonder which mask to wear during haze season or travel in heavy air polluted city, not every mask can serve the right purpose.
First we have to know the haze consists of fine particles that has the size of less than 2.5 micrometers/microns (0.00025 cm), also known as PM2.5 (PM = Particle Microns). Fine particles of PM2.5 also applied to most type of combustion gases (CO2, SO2, NO2, etc) from forest fire, motor vehicles gases, open space wood burning, and etc. Look at the visual photo below to imagine the difference in size when compare to a typical human hair. The size of 2 microns is so so tiny.
The correct mask to use is N95 mask that can cover tightly we you wear it on. When wearing N95 mask, it has to be tightly seal around the face. Surgical mask has loosen end and will not provide protection against PM2.5 particles. This is one of the distinguish difference between the 2 type of mask also.
When fine particles successful pass through your nostril and enter your lung, it will be deposit on the alveoli and causing long term effect. Some individual who have constant exposure without protection can even suffer from cardiac pulmonary disease causing sudden lung and hearth failure. In U.S. (United Stated) the fine particle can be much smaller than those in China. Thus it is important to get a good grade N95 mask.
You may check your city’s air pollution index (API) at here http://aqicn.org, and it is always important to stay alert whether API dangerous level has his your city and prepare the proper protection gear for yourself and family members.