Temporal variation of dose rate distribution around the Fukushima Daiichi nuclear power station using unmanned helicopter

Appl Radiat Isot. 2016 Dec:118:308-316. doi: 10.1016/j.apradiso.2016.09.008. Epub 2016 Oct 3.

Abstract

Aerial radiological survey using an unmanned aerial vehicle (UAV) was applied to measurement surface contamination around the Fukushima Daiichi nuclear power station (FDNPS). An unmanned helicopter monitoring system (UHMS) was developed to survey the environmental effect of radioactive cesium scattered as a result of the FDNPS accident. The UHMS was used to monitor the area surrounding the FDNPS six times from 2012 to 2015. Quantitative changes in the radioactivity distribution trend were revealed from the results of these monitoring runs. With this information, we found that the actual reduction of dose rate was faster than the one calculated with radiocesium physical half-life. It is indicated that the attenuation effect of radiation by radiocesium penetration in soil is dominant as for reason of reduction of dose rate.

Keywords: Fukushima Daiichi nuclear power station; Radiation measurement; Radioactive cesium; Unmanned aerial vehicle.

MeSH terms

  • Aircraft / instrumentation*
  • Equipment Design
  • Equipment Failure Analysis
  • Fukushima Nuclear Accident*
  • Japan
  • Nuclear Power Plants*
  • Radiation Dosage
  • Radiation Monitoring / instrumentation*
  • Radiation Monitoring / methods*
  • Radioactive Fallout / analysis*
  • Spatio-Temporal Analysis*

Substances

  • Radioactive Fallout