Dr. Tsubokura's Radiation Lecture Vol.32

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

63. Air dose rates are not consistent

"External exposure" occurs when the body is exposed to radiation originating from an external source. Glass badges and monitoring posts are used to measure the radiation.

The level of external radiation, measured by a device called dosimeters, does not remain the same over time, as radiation is not emitted at a regular pace. The emission of radiation occurs similarly to how sparklers give off sparks. If radioactive substances were sparklers, the fireball would be the nucleus and sparks would be ionizing radiations. In the same way that sparks come off randomly, in different directions, ionizing radiations are emitted inconsistently. Consequently, the levels of detected external radiation fluctuate. Therefore, the external radiation level can be determined by measuring repeatedly or calculating the average value over a fixed period.

Moreover, the measurement for external ex