Stress and Strain Wearing Compressed Air-Breathing Apparatus

Abstract

Abstract This paper describes a study carried out among 44 employees who use breathing apparatus in the form of compressed air masks during their work. The purpose of the study was to determine the extra load caused by working with compressed air masks during the performance of (simulated) tasks. The average exertion level demanded by the four tasks varies from 30% to 93% of the maximum load during cycle ergometry. The data relating to the extra load are obtained by recording heart rate using the Sporttester PE 3000 and by measuring oxygen uptake using a modified Oxylog apparatus. The duration of the tasks is also recorded. The study results show that at a low level of exertion when working with compressed air equipment, the extra load gives no special cause for concern. At high exertion levels, the subjects adapt to the increase in the external load by taking more time to perform the task. This increase in the external load has the additional effect of reducing the available reserve capacity (cardiovascular and energetic). When rescuing a victim, this could mean that the operation takes longer when compressed air mask equipment is used;it is then in the interests of both the victim and the rescue worker with breathing apparatus that the latter has an excellent physical work capacity.