Approach for the Calculation of the Standard Limits (1/2)

This figure shows the approach for the calculation of the standard limits, explaining the relation between the annual additional dose limit (1 mSv) and the standard limit for general foods (100 Bq/kg).

First, the annual permissible dose allocated to general foods is assumed to be 0.88 to 0.92 mSv by subtracting approx. 0.1 mSv permitted for drinking water from the total annual permissible dose of 1 mSv. Next, domestically-produced foods and imported foods are assumed to account for 50% each of all distributed foods. Then, in the case of males aged between 13 and 18, it is assumed that 374 kg of foods or 50% of the total annual consumption per person (approx. 748 kg) is domestically produced. The effective dose coefficient in consideration of the effects of all covered radionuclides (0.0000181 mSv/Bq) is to be used for calculation.

Then, the calculation formula is as follows.

0.88 mSv = (Radioactivity concentration: Bq/kg) × 374 kg × 0.0000181 (mSv/Bq)

(Radioactivity concentration: Bq/kg) = 120 Bq/kg

If radioactivity concentrations in general foods do not exceed 120 Bq/kg, the annual additional dose will be within 0.88 mSv.

Therefore, the standard limit for general foods (100 Bq/kg), which is lower than 120 Bq/kg, is the value set on the safe side to guarantee safety.

• Included in this reference material on March 31, 2013
• Updated on January 18, 2016