White Paper - 11. Bring peace of mind to radiation-protection policy

Page / - last modified by Ad Min on 2021/04/24 22:49

11. Bring peace of mind to radiation-protection policy

last modified by Ad Min

on 2021/04/24 22:49

Table of Contents

In the nuclear sector, two issues play a major role: radiation protection and continuous improvement. Underlying these issues is a third principle: LNT, which stands for Linear No Threshold. In this section we briefly explain how these issues are related and affect the nuclear industry.

Radiation protection is based on the following principles: Justification, Optimization and Dose Limits. Justification is about whether you can apply radiation in society at all (ethically). Our rules are clear about this: the generation of energy by nuclear fission is justified.

Next, it is important to optimize radiation exposure. The word ALARA (As Low as Reasonably Achievable) is often used in this context. Socio-economic factors must be considered. Many people confuse ALARA with 'as low as possible', but it is precisely by taking socio-economic factors into account that an optimal level of exposure is created, where lowering exposure even further makes no sense, and is not desirable. The dose limits are there to protect the population (1 mSv per year) and employees (20 mSv per year) from a high radiation dose caused by licensed activities. These values have been established internationally. Exceeding those limits is equivalent to a violation of the law. Are ALARA and Linear No Threshold (LNT) a recipe for continuous improvement?

In the nuclear industry, the principle of continuous improvement (according to Plan-Do-Check-Act) is also of great importance, especially in the field of reliability and safety. Whereas ALARA is wrongly seen by many people as a 'race to zero millisievert', continuous improvement is wrongly seen as a 'race to the top'. The PDCA cycle applied to business operations (efficiency in production) has a built in brake: the costs of efficiency must outweigh the additional yields. But safety can always be improved and—in the eyes of many people—is 'unaffordable', so one loses sight of the fact that even what is 'safe' is tied to socio-economic factors. Safety should also be based on an optimization principle, sometimes referred to as SAHARA (Safety as High as Reasonably Achievable).

The LNT hypothesis states that radiation creates a chance of cancer, and that this chance increases linearly with the dose: twice as much dose, twice as likely. According to LNT, there is no threshold where the probability becomes zero. So even the tiniest amount of radiation could technically lead to death, LNT says.

In practice, the LNT & ALARA have resulted in a loss of proportionality within the safety requirements. Often there is a lack of optimization because the aim is to achieve the highest safety and lowest radiation dose (because of LNT), while socio-economic factors play too small a role in the process.

Moreover, this correlates with a broader trend in our society: increasingly rejecting any risk (see, for example, current issues such as the discussion around PFAS and those around Tata Steel), rather than seeking a compromise possible disadvantages for residents and more-than-likely benefits for the economy & society. In the case of nuclear energy, the danger perceived by the public is much greater than the danger assessed by experts. This leads to stricter policies guided by an irrational population rather than evidence-based analysis. Finally, setting standards takes several steps, including the use of models. Uncertainties throughout this process are conservatively estimated. This leads to 'stacking of conservatism' —in other words, the norm becomes much stricter than is necessary to achieve a desired level of protection.

This desired level of protection itself can also be questioned. Do the [safety] requirements imposed on the use of radiation and nuclear energy offer the same level of protection to the population as is required of other branches of industry? In other words, are the standards set for nuclear energy proportional to actual risk? We therefore recommend that the government sets a standard that is optimized and acceptable.