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Table 1 Monitored variables during two 5 min tests within the open and sealed HEF

From: A novel application of capnography during controlled human exposure to air pollution

Variable Label
Identification and class variable  
   ID Subject ID #
   EXP Test number (1-first or 2-second)
EtCO 2 wave parameters  
   POINTS Number of CO2 measurements (20 samples/second) per one respiratory cycle
   tot_len Total time from STARTPOINT to ENDPOINT (seconds)
   tot_AUC Cross sectional area under the curve depicting detectable CO2 (mm Hg X seconds)
   len2 Time from STARTPOINT to start of alveolar plateau (seconds)
   slope2 Slope from STARTPOINT to start of alveolar plateau (mm Hg/second)
   diff2 CO2 absolute change from STARTPOINT to start of alveolar plateau (mm Hg)
   len3 Time from start to end of alveolar plateau (seconds)
   slope3 Slope from start to end of alveolar plateau (mm Hg/second)
   diff3 CO2 absolute change from start to end of alveolar plateau (mm Hg)
   EtCO2 End tidal CO2 (maximum expired CO2 (mm Hg)
   AUC3 Cross sectional area under the alveolar plateau (mm Hg X seconds)
EtCO2 Wave Signal Statistics  
   MIN Minimum (lowest) CO2 value from STARTPOINT to ENDPOINT
   MAX Maximum (highest) CO2 value from STARTPOINT to ENDPOINT
   CORRMAX Maximum (highest) CO2 value corrected for minimum (zero) value
   MEAN Mean CO2 value from STARTPOINT to ENDPOINT
   MED Median CO2 value from STARTPOINT to ENDPOINT
   STDEV Standard deviation of mean CO2 value from STARTPOINT to ENDPOINT
   RMS (true) Root mean square of CO2 values from STARTPOINT to ENDPOINT
Minute Ventilation Variables  
   RR Average respiratory rate (breaths/minute)
   VTE Average expiratory tidal volume (liters/BTPS)