6-4 
No.  Calibration Item  Function Description  Calibration Occasion   
3  Flowmeter zeroing 
(user) 
Calibrates zero offset in 
the flowmeter. 
Zero offset exists in the 
flowmeter.   
The monitored value deviates 
from the total flow setting by 100 
ml or 5%, whichever is larger; or 
the monitored value deviates from 
the limb flow setting by 50 ml or 
5%, whichever is larger. 
The flowmeter still displays a 
flow reading after all fresh gases 
4  High-flow O2 supply 
zeroing (user) 
Calibrates zero offset in 
the high-flow O2 supply 
module. 
1.  Zero offset exists in the high-flow 
O2 supply module (the monitored 
value deviates from the total flow 
setting by 2 L or 10%, whichever 
is larger). 
2.  The high-flow O2 supply module 
is replaced. 
5  Pressure calibration 
(service) 
Calibrates the pressure 
sensor and PEEP valve 
of the anesthesia 
machine. 
1.  The VCM is replaced. 
2.  The expiratory valve assembly is 
replaced. 
3.  The sensor adapter board is 
replaced. 
4.  The measured value of the 
machine's pressure sensor 
deviates from that of the standard 
pressure gauge by 5% of the 
reading or 2 cmH2O, whichever is 
larger. 
6  Expiratory valve 
calibration (service) 
Calibrates the expiratory 
valve of the anesthesia 
machine. 
1.  The VCM is replaced. 
2.  The drive gas assembly is 
replaced. 
3.  The sensor adapter board is 
replaced. 
7  Pressure and flow 
zeroing (service) 
Calibrates zero offset in 
the VCM and VPM. 
The flow or pressure waveform 
deviates from the baseline. 
8  Total flow sensor 
calibration (service) 
Calibrates the total flow 
sensor of the electronic 
flowmeter and obtains 
the N2O factor of the 
sensor. 
1.  The N2O factor of the total limb 
O2 flow sensor is excessively 
large. 
2.  The flow sensor is replaced. 
The electronic flowmeter board is