The use of inductive plethysmography in the study of the ventilatory effects of respirator wear.
Stark-GP; Hodous-TK; Hankinson-JL
Am Ind Hyg Assoc J 1988 Aug; 49(8):401-408
A study of the ventilatory effects of respirator wear utilizing inductive plethysmography was conducted. Male volunteers performed graded exercise on a treadmill, consisting of standing in place or walking at 4.8 kilometers per hour at grades up to 12 percent while wearing a portable respiratory inductive plethysmograph (RIP) with or without an oral mouthpiece with pneumotachograph or a half face twin cartridge respirator. Respiration rate, tidal volume (VT), ventilation, inspiratory time/total conspiratory and expiratory time (TI/Ttot) ratio, fraction of VT accounted for by rib cage volume (VOL RC/VT), and heart rate were monitored. The data obtained by the RIP were compared with that obtained by the pneumotachograph. The mean percent error of the RIP data compared with the pneumotachograph data over all exercise levels was -3.16 percent and the relative standard deviation was 11.26 percent. The large standard deviation indicated a large variability for each subject at each exercise level. Respiration rate was decreased and VT and ventilation were increased when the respirator plus RIP were worn. Wearing the RIP alone or the RIP plus pneumotachograph during exercise did not affect any of the measured parameters. At rest the TI/Ttot ratio was increased when the pneumotachograph or respirator was used. During exercise the TI/Ttot ratio was increased when wearing the respirator compared to wearing the RIP alone or the pneumotachograph. VOL RC/VT was significantly decreased during exercise when the RIP plus respirator was worn compared to the RIP plus pneumotachograph. Heart rate was not significantly affected by any of the protocols. The authors conclude that although the portable RIP can measure accurately group mean ventilation parameters, it has substantial variability that limits its ability to measure individual ventilation parameters accurately.
NIOSH-Author; Pulmonary-function; Equipment-reliability; Laboratory-testing; Respiratory-protection; Physical-exercise; Personal-protective-equipment
American Industrial Hygiene Association Journal