Try to choose medical masks. Cao Jingui, director of the Infection Control Department of the Air Force General Hospital, said that medical masks are mainly divided into three categories: medical protective masks, surgical masks, N95 and N99 masks. These three types of masks have three layers, the outermost layer is splash-proof, the middle layer is filtering, and the innermost layer is moisture-proof. These medical masks are effective in preventing respiratory diseases, while cotton masks on the market only have dust-proof function. Most cartoon masks sold in some stalls have no regular manufacturers. If you wear it often, it will not only keep warm and isolate dust, but will stimulate the lungs and even cause respiratory diseases. Therefore, Director Cao suggested that citizens should try to choose professional masks when going out. "Medical masks are approved by the state and licensed, and citizens in the market are still cautious in buying them." Wear a mask and change the boiling water every day. The medical staff of the emergency center reminded the public that foggy days will hinder normal blood circulation, leading to cardiovascular diseases, hypertension, coronary heart disease, cerebral hemorrhage and respiratory diseases. Suggestion: The elderly and infirm, patients with cardiovascular diseases and young children should go out less and have to go out. You'd better wear a mask. It is best to change the mask every day and put it in boiling water for disinfection when cleaning. At the same time, don't spray perfume on the mask, so as not to stimulate the respiratory system and induce respiratory diseases. Lu, chief physician of respiratory department of Chengdu Women and Children Central Hospital, said that the number of patients with respiratory diseases has increased due to the smog weather. "In the last month or two, many children have caught a cold several times in a row, all of which are respiratory diseases." Lu suggested that indoor temperature and humidity should be kept as high as possible, and the temperature should be kept at around 24 degrees. It is advisable to keep the humidity around 50% and 60%. Rooms should be properly ventilated, especially in families with air conditioning and heating. But when opening the window, try to avoid the morning and evening smog peak hours. It will be better to open the window in the afternoon, which lasts about half an hour. Turn on fog lights on the road and don't stop outdoor exercise and fitness with high beam, depending on the environment. In foggy days, susceptible people, patients with cardiovascular and cerebrovascular diseases and respiratory diseases should not exercise, and should try to reduce going out. If you need to go out, try to choose 10 from the morning to 3 pm to avoid going out in the morning and evening. In addition, those who have exercise habits at ordinary times should stop running and walking outdoors, try to choose relatively mild indoor exercise, and strenuous cardiopulmonary exercise should be temporarily stopped. It is best not to do cardiopulmonary exercise, especially high-intensity treadmill or bicycle exercise. Hazy weather and extremely low air quality may cause acute upper respiratory tract infection. At the same time, due to the reduction of sunshine, the production of vitamin D in the body is insufficient, and the absorption of calcium is also greatly reduced. Dietotherapy experts in China suggest that citizens eat more "stewed lily with Sydney" to moisten their lungs and resist viruses, and "stewed radish with beef" to enhance their immunity. (Wen Song)