(1) Put one hand on the injured person's forehead and press down to make his head lean back. While keeping the respiratory tract clear, the thumb and forefinger of the hand pressing the forehead hold the nostrils on both sides, and the forefinger and thumb of the other hand are placed on the mandible to lift it upward.

⑵ Take a deep breath, tightly wrap the patient's lips with your lips, and blow smoothly, taking care not to leak. Blow air into the patient's mouth to the lungs under the operation of keeping the respiratory tract unobstructed. If the blowing is effective, the chest of the wounded and sick will expand up and down with the discharge of gas.

(3) After blowing, the lips leave, and the fingers holding the nose are released, so that the gas can be exhaled. At the same time, turn the side head to inhale fresh air and blow it again.

⑷ Blow air into the lungs for 2 seconds for adults and 1 sec to 1.5 sec for children. Blowing volume per time: 700- 1 100ml, with an average of 900ml. Frequency: adults 12 times/minute, children 20-40 times/minute. The younger the age, the higher the frequency.