Japan’s Nuclear Regulation Authority to Increase Emergency Radiation Exposure Limit

World Nuclear News reported that Japan’s nuclear regulator plans to increase the radiation exposure limit for workers in emergency situation from the current level of 100 millisieverts (mSv) up to 250 mSv.

As quoted in the market news:

The Nuclear Regulation Authority (NRA) said in a statement today that it will increase the exposure limit from April 2016.

Normally nuclear workers are allowed to receive a dose of 20 mSv per year, although in practice they often receive very much less. If that limit is exceeded in any year, the worker cannot undertake nuclear duties for the remainder.

In emergency circumstances, safety regulators allow workers to receive up to 100 mSv with the same conditions applying, that they must leave the site should that limit be reached. The 100 mSv level is roughly the point at which health effects from radiation become more likely. Below this it is statistically difficult to connect radiation dose to cancer rates, but above this the relationship starts to become apparent.

Under a special allowance from the then-regulator, the Nuclear and Industrial Safety Agency, workers at Fukushima Daiichi were permitted doses of up to 250 mSv. That limit was lowered back down to 100 mSv in December 2011.

Click here to read the full World Nuclear News report.