Pulmonary and heart rate responses to wearing N95 filtering facepiece respirators

BackgroundFiltering facepiece respirators are the most common respirator worn by US health care and industrial workers, yet little is known on the physiologic impact of wearing this protective equipment.MethodsTwenty young, healthy subjects exercised on a treadmill at a low-moderate (5.6 km/h) work rate while wearing 4 different models of N95 filtering facepiece respirators for 1 hour each, 2 models of which were equipped with exhalation valves, while being monitored for physiologic variables.ResultsCompared with controls, respirator use was associated with mean 1 hour increases in heart rate (range, 5.7-10.6 beats per minute, P < .001), respiratory rate (range, 1.4-2.4 breaths per minute, P < .05), and transcutaneous carbon dioxide (range, 1.7-3.0 mm Hg, P < .001). No significant differences in oxygen saturation between controls and respirators were noted (P > .05).ConclusionThe pulmonary and heart rate responses to wearing a filtering facepiece respirator for 1 hour at a low-moderate work rate are relatively small and should generally be well tolerated by healthy persons.