16-8 
 
16.6.8 Setting Humidity Compensation 
The CO
2
 modules is configured to compensate CO
2
 readings for either Body Temperature 
and Pressure, Saturated Gas (BTPS), to account for humidity in the patient’s breath, or 
Ambient Temperature and Pressure, Dry Gas (ATPD). 
  ATPD: 
100/%)()(
22 ambco
PvolCOmmHgP u 
 
  BTPS: 
100/)47(%)()(
22
u 
ambCO
PvolCOmmHgP
 
Where, 
2CO
P
= partial pressure, 
%vol
= CO
2
 concentration, 
amb
P
= ambient pressure, and unit 
is mmHg. 
 
To set the humidity compensation:   
1.  Select the CO
2
 parameter area or waveform area to enter the [CO2 Setup] menu. 
2. Select [BTPS Compen] and then toggle between [On] and [Off]. 
  Switch on for BTPS. 
  Switch off for ATPD. 
 
 
16.7 Calibrating the CO
2
 Module 
A calibration should be performed once a year or when the readings go far beyond the range. 
For details, refer to 25 Maintenance.