Abstract
The objective of this study was to clarify the effect of increasing UTCI by a bonfire outdoors. Measurements were carried out at a public accommodation located in Kasugai City, Aichi, on the night of September 19, 2020. Two bonfires were performed using firewood mainly made of pine. During the bonfires, thermal environmental factors were measured around the bonfire. Following findings were obtained. The bonfires raised the air temperature at a point (1.1 m above the ground) 1.5m from the heat source by a maximum of 3.5 °C to 3.9 °C, and raised the globe temperature by a maximum of 4.7 °C to 6.1 °C. At the same point 1.5m from the heat source, the bonfires raised the plane radiant temperature facing the heat source by up to 32.5 °C to 36.3 °C, the UTCI for the body facing the heat source by 8.4 °C to 9.6 °C, and the UTCI for the whole body by 3.7 °C to 5.2 °C. Meanwhile, no thermal effect of the bonfires was observed in the direction opposite to the heat source. The effect of increasing UTCI by the bonfires decreased as the distance from the bonfire increased.
https://ror.org/02cntp233 
