Improper use of humidifiers may lead to lung damage, especially when bacteria and impurities contained in the water enter the air along with water vapor. When the human body inhales air containing bacteria and impurities, it may cause respiratory infections and even lead to lung damage. Humidifier pneumonia is mainly caused by the lack of cleaning of the humidifier, which leads to the invasion of contaminated microorganisms into the human respiratory system, triggering a type of allergic pneumonia. This type of allergic pneumonia caused by humidifiers is different from bacterial pneumonia and viral pneumonia. If the patient has a cough, fever, especially shortness of breath, chest tightness symptoms, you should go to the hospital in time for treatment. Special attention: try to add sterilized water, pure water, and can not just add lemon juice, essential oils, biocides; regular cleaning of the humidifier, clean up the frequency of the need for 3 to 5 days a time; long time no use of the humidifier should be kept clean and dry.