1. Reduce the outdoor detention time and wear a mask when going out. Minimize going out and outdoor activities in foggy days, especially don't do outdoor sports. If you have to go out, you'd better wear a mask. In smoggy weather, the indoor PM2.5 concentration is significantly lower than that outside. Even in ordinary buildings, the indoor PM2.5 concentration is about 50% to 80% of that outside, so it is relatively safer to stay indoors. Turn left | turn right 2. Wash your face, rinse your mouth and clear your nose when you come out. Introduce a simple and easy-to-learn method: wash your hands, hold warm water, gently absorb water through your nose and blow your nose quickly, and repeat it several times, and all the dirty things in your nasal cavity will be cleaned up. It should be noted that when cleaning the nasal cavity, you should gently absorb water to avoid coughing. Secondly, we should pay attention to vitamin supplementation, have a light diet, and eat more fruits and vegetables, especially pears, loquats, oranges, oranges and other fruits that clear the lung and resolve phlegm. 3. Reduce window ventilation. PM2.5 in the air diffuses quickly. When there is fog, window ventilation will make indoor PM2.5 rise rapidly, so the number and time of window ventilation should be minimized. If you want ventilation, try to choose at noon and avoid morning and evening.