APPLICABILITY OF AUTONOMOUS UNMANNED HELICOPTER SURVEY OF AIR DOSE RATE IN SUBURBAN AREA

Abstract

An autonomous unmanned helicopter (AUH) survey is a useful tool for monitoring the distribution of ambient dose equivalent rates. However, the AUH survey method was developed for plane permeable fields such as agricultural land, and its applicability to urban areas is unclear. In this study, the applicability was investigated by comparing the results of AUH and ground-based surveys conducted in suburban areas, including residential and agricultural lands. The results of both surveys broadly agreed with each other within a factor of 2 in the range independent of land use, and the factor was the same as that reported for plane permeable fields. These results suggest that AUH surveys are applicable in urban areas. The measurement uncertainty of the AUH survey was largely affected by the patchy and local distribution of ambient dose equivalent rates on the ground and differences in the fields of view, rather than land use.