There are many ways to self-test lung function, mainly from clinical symptoms, respiratory rate, exercise endurance and other aspects of self-test. 1. Clinical symptoms: Observe whether there are symptoms such as cough, sputum, chest tightness, shortness of breath, dyspnea, etc. If the above symptoms occur, it generally suggests the presence of lung diseases. If sputum is coughed up, the type of infection can be initially judged according to the color of the sputum, such as brick-red sputum is commonly found in Klebsiella pneumoniae infections, rust-colored sputum is commonly found in Streptococcus pneumoniae infections, and so on. 2. Respiratory rate: In the resting state, the normal adult respiratory rate is generally 12-20 times/minute, observe whether your respiratory rate is too fast or too slow. You can also observe the depth of your breathing. Deep and fast breathing can be seen in metabolic acidosis, respiratory alkalosis, etc. Shallow breathing can be seen in pulmonary edema and pneumonia. 3. Exercise endurance: walk as far as possible within 6 minutes, stop immediately if dyspnea or chest pain occurs, and record the maximum walking distance. Normal people are generally greater than 450 meters, if less than 450 meters suggests mild cardiopulmonary insufficiency, if less than 150 meters suggests severe cardiopulmonary insufficiency. The above lung function self-test small method can only be used as a reference, if you want to understand the specifics of lung function, to the regular hospital visits, relevant examinations, if found lung disease should be timely compliance with the doctor’s instructions for treatment.