Fig 1.
Diagram of the cooling device developed in this study.
PAPR: powered air-purifying respirator.
Fig 2.
Photograph of the cooling device.
PAPR: powered air-purifying respirator.
Fig 3.
Outline of the experiment for the measurement of the workloads at the maximal oxygen uptake.
80% THR: 80% of the target heart rate.
Fig 4.
Outline of the experiment for the measurement of temperature.
Cold artificial climate chamber: dry-bulb temperature of 28°C and relative humidity of 45%, RPD: respiratory protective device; hot artificial climate chamber: dry-bulb temperature 36°C and relative humidity 45%; VO2max: maximal oxygen uptake.
Fig 5.
Photograph of the experiment for the measurement of temperature.
The subject exercised using the cycle ergometer in a hot artificial climate chamber set at a dry-bulb temperature of 36°C and relative humidity of 45%. The image shows a subject wearing a powered air-purifying respirator equipped with a cooling device.
Fig 6.
The ambient air temperature and temperature near the powered air-purifying respirator inlet in the container of the cooling device were measured. The measured values of the time taken to move to the next room were excluded; C-PAPR: temperature near the powered air-purifying respirator inlet in the container of the cooling device.
Table 1.
Inhalation temperature.
Fig 7.
The temperature was calculated as the difference between the temperature value at minute 0 and at the minute studied. The measurement values for the time taken to move to the next room were excluded. *Temperature of the RPR was significantly lower than that of PAPR, **temperature of C-PAPR was significantly lower than that of PAPR and RPR. C-PAPR: powered air-purifying respirator equipped with cooling device; PAPR: powered air-purifying respirator; RPR: replaceable particulate respirator.
Table 2.
Rectal temperature.