In Japan, the maximum annual individual radiation exposure dose for an individual was 1 mSv before the Fukushima Dai-ichi nuclear accident. The 1 mSv included exposure to artificial sources of radiation, such as medical exposure, not taking into consideration exposure to natural background radiation from the Earth and the Universe.
After the Fukushima accident, the regulatory dose limit was initially raised to 20 mSv per year for all age groups. It was later lowered to 5 mSv per year for children.
Ian Goddard, in his video “Fukushima Radiation NOT SAFE,” mentions a study done on over 400,000 nuclear workers from 15 countries, which was the largest nuclear worker study ever conducted, involving 51 radiation scientists.
“Fukushima Radiation NOT SAFE”
The papers related to the study mentioned above are these:
The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: Estimates of Radiation-related Cancer Risks
The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: Design, Epidemiological Methods and Descriptive Results
Average individual annual radiation exposure doses were calculated from data found in Table 5 of the second study listed, and the results were tabulated and highlighted for easy referencing.
Average individual annual radiation exposure dose in nuclear workers in 15 countries
In Japan, an average individual annual dose for nuclear workers was 2.33 mSv: less than a half of the current “temporary” regulatory dose limit for Japanese children, which is 5 mSv; and almost one-tenth of the current “temporary” regulatory dose limit for adults, which is 20 mSv. An overall average was even lower at 1.85 mSv.
In other words, Fukushima residents are being exposed to radiation doses that average nuclear workers are not even allowed to receive. In some areas with high ambient radiation levels, actual annual exposure will be higher than regulatory dose limits when taking into consideration internal radiation exposure from contaminated food and water.
This article features a few images of Geiger counter readings from a Date-city, Fukushima, elementary school. There are many other places with such micro hotspots in Fukushima and surrounding prefecture, or even in Tokyo Metropolitan region.
In conclusion, the regulatory annual dose limits of 5 mSv for children and 20 mSv for adults in Japan are much higher than the actual average individual annual dose of 2.33 mSv in Japanese nuclear workers or 1.85 mSv in overall average, which was associated with an increased cancer risk in adult nuclear workers.
How the average individual annual dose was obtained:
From Table 5 Extended in the study, as shown below, an average cumulative dose (mSv) was divided by an average individual cumulative dose (years) to obtain an average individual dose per year for each country, which is listed in the right column of the table above.
You can calculate your annual exposure from this ”Radiation Dose Chart.”