In order to monitor whether there are any effects due to radiation from its activities, a continuously measuring the amount of radiation in the environment using monitoring posts are installed to several sites.
This environmental radiation which ORDC measures is the airborne radiation in units of uGy/h (micrograys per hour). The airborne radiation level around ORDC is generally measured to be (3 - 4) x 10-2uGy/h. However, rainfall and other influences can change the level up to two-fold.
Radiation surrounding us
In our every day lives, we are constantly receiving radiation. The amount of radiation received by a person's body is expressed in units of mSv (milliSeiverts). This radiation comes from cosmic rays from space, from earth, and from natural radioactive substances in food. This radiation amounts to about 1.1 mSv per person per year. (Excluding radiation from naturally occurring radon, 1.3mSv/y). Besides this, radiation is received from other sources such as from hospital x-ray examinations and from nuclear power plant operations. This type of radiation is called man-made radiation.
Natural radiation level depending upon location
How much radiation we receive depends upon where we are. For example, in Japan, the amount of radiation in the Kansai area is generally higher than in the Kanto area. This is due to differences in the earth's composition.
If a person were to move from Tokyo to Osaka, that person would come to receive 0.17mSv more radiation per year, however this would have absolutely no ill effects. Nuclear power plants have established a goal of releasing no more than 0.05 mSv per year; this is lower than what would be obtained by moving from Tokyo to Osaka.
Also, the amount of radiation received from cosmic rays depends upon elevation. For example, if a person were to stand on the peak of Mt. Fuji, that person would receive five times more radiation than when standing at ground level.