*Simulating standard open airway *External breast compression: display device and alarm device *Indicator light display of correct and wrong compression ; alarm of wrong compression *Intensity display of correct (1-2 cm) and wrong (<1cm or >2cm) compression; alarm of wrong compression *Artificial respiration (inhalation): display device and alarm device *Inhalation <30ml or > 50ml, wrong indicator light display and alarm prompting; Inhalation between 30-50ml right indicator light display *Inhalation too quickly or too much result in air entering into stomach; indicator light display and alarm prompting
*Operating cycle: one cycle includes five times of 30:2 or 15:2 ratio of compression and artificial respiration. *Examination of brachial artery response: pinch the pressure ball by hand and simulate brachial artery pulse