5-4
5.1.8 CO2
1. Test fixture
CO2 steel bottle (containing 10% CO2)
2. Test procedure
①Sidestream CO2 measurement: Set the calculation compensation of DPM4 to COMMON.
Plug the water trap to the water trap socket, connect the sampling tube with the CO2 steel
bottle, and open//close the valve of the CO2 steel bottle based on the interval of 3s. The
CO2 value should be the calibration gas pressure value: 76±5%mmHg. When the valve is
opened permanently, the patient monitor prompts “APNEA ALARM”.
Unplug the water trap. The patient monitor prompts “CO2 water trap OFF”. Plug the water
trap again. The prompting message disappears.
②When the measured value exceeds the high limit of CO2, the patient monitor prompts “CO2
too high” on the main screen. When the measured value is lower than the low limit, the
patient monitor prompts “CO2 too low”.
5.1.9 Watertrap
1. Connect the airway and block the inlet of the sampling line with your finger. Check if the
message CO2 SAMPLE LINE ABNORMAL is displayed and the current pump rate in the
CO2 USER MAINTAIN menu drops below 5ml/min. If yes, it indicates the airway is
normal. Otherwise, proceed with step 2.
2. Remove the sampling line and block the inlet of the watertrap with your finger. Check if the
message CO2 SAMPLE LINE ABNORMAL is displayed and the current pump rate in the
CO2 USER MAINTAIN menu drops below 5ml/min. If yes, it indicates there may be a
problem with the connection between the sampling line and watertrap or a leakage in the
sampling line. Otherwise, proceed with step 3.
3. Remove the watertrap and block the two inlets in the receptacle for the watertrap. Check if
the message CO2 SAMPLE LINE ABNORMAL is displayed and the current pump rate in
the CO2 USER MAINTAIN menu drops below 5ml/min. If yes, it indicates there may be
a problem with the connection between the watertrap and its receptacle or a leakage in the
watertrap. Otherwise, there may be a problem with the internal airway in the monitor. The
internal airway has two parts, one part in the receptacle and the other part in the module.
Block the small tubes between the watertrap receptacle and module with your fingers and
check if the message CO2 SAMPLE LINE ABNORMAL is displayed and the current pump
rate in the CO2 USER MAINTAIN menu drops below 5ml/min. If yes, it indicates there is
a problem with the airway in the receptacle. Replace the receptacle. Otherwise, replace the
module.