Objectives: This research reports on the workplace evaluation of in workplace breathing rates for negative pressure RPD's across varying work rates in the Australian Metalliferous Mining Industry.
Methods: Smelter workers wore their normal negative pressure RPD's and performed their normal work duties across an entire shift whilst their breathing rates, heart rate and core temperature was monitored for comparison with the recommended limits in ISO/TS 16976-1.
This research was made possible by the recent development and validation of a portable personal data-logger to measure breathing rates through a respirator whilst workers perform normal work activities. See previous methodology paper from ISRP 2016: http://ro.uow.edu.au/cgi/viewcontent.cgi?article=3759&context=sspapers
Results: It was found that the higher the work rate experienced, the more pronounced the effects of RPD use and the more distinct the changes in breathing pattern became. The physiological effects and perceived burden of use also became more pronounced.
The results provide the first real time analysis of breathing rates of negative pressure RPD wearers performing normal duties in a smelter workplace. Interestingly, they were not always consistent with those specified in ISO standards that had been primarily determined from laboratory tests.
Conclusions: Whilst laboratory tests give an indication of the use of respiratory protection it is no substitute for workplace studies where the study participants are seasoned RPD users and perform their normal work duties. Studies which use simulated activities and non industry cohorts should also be critically evaluated to discern whether they are truly representative of the workplace use of RPD’s.
Wearers of RPD’s at higher work rates are under considerable strain and RPD programmes should consider the individual’s physiological capacity, as well as the work rates the wearer will be subjected to in the course of their work activities.
It is envisaged that this research will inform international standard development and end users in the appropriate selection and use of respiratory protection and assist in improving the respiratory and cardiovascular health of workers in heavy industry.