In this experiment, the author investigated the changes of blood and urine of the rescue team workers engaging in heavy tasks in high thermal conditions, in addition to the reaffirmation of the previous results. Further, he encountered several cases of heat stroke occasionally.
The followings were the results obtained:
1. Change of pulse pressure which the results were obtained previously was affirmed statistically by increasing the number of the cases.
2. The cases of heat stroke suggested that the threshold limit of the increase of pulse pressure seemed to exist around the rate of 150%.
3. The threshold limit of body temperature (under tongue) was around 39°C.
4. By remarkable sweating after the task, blood was concentrated, resulting the increase of specific gravity of the total blood, proteine in plasma, hematocrit value and hemoglobin content.
5. The group of heat stroke showed higher pulse pressure, higher pulse rate, higher temperature under the tongue and has a tendency of a higher rate of blood concentration.
6. Life-saving mask type 4 produced heat when soda lime absorbed CO2 expired in the circulaing air. But the influence of the high temperature and high humidity of the environment was greater than the heated air-input of the mask.
7. The limitation of the continuity of the task in such a high thermal condition seemed to be around 30 minutes. The resting time was needed at least 90 minutes for adequate recovery.