Abstract
The conventional radiation tolerance criterion of people for the evacuation planning in city fire, taken for 2050kcal/m2h (2.38kW/m2), was determined after the wartime test, where are assumed some problems in radiation measurement.
This report aims at examining this criterion, and an attempt was made to measure the endured time of the subjects exposed opposite to radiation heating panel. The posture of the subjects was determined supposing that it would be most disadvantageous for people in big fire, and the endured time is defined here as the time until a subject gets away according to his own judgement. These test conditions are almost similar with those of the wartime test of Usui. As shown in Fig. 3, our test result indicates that the endured time of each subject for a radiation intensity is much longer than that of the wartime tests. However, regarding that the endured time generally drops very rapidly between about 1800kcal/m2h and 2300kcal/m2h, the radiation tolerance criterion as an engineering index for evacuation planning should be taken for a value safer than the conventional criterion.
The temperature of cheak surface of each subject was also measured with radiation thermometer, and it was found that the cheak surface temperature drops quite rapidly by the sweating on face. Though the pre-pain time of our tests agrees considerably well with those of the classical physiolosical studies by Buettner and Hardy, it was found that the endured time in our sense is much longer than the pre-pain time.
