Radiation & Environment - Radiation protection - standards
NRG has for many years provided advice to government, and public and private institutions on the interpretation and application of radiation protection standards, in both the nuclear and other fields. This includes assistance in developing safe systems of work, specification of appropriate equipment for measurement of radiation and for protection of personnel. NRG also provides comprehensive training programmes on all aspects of radiation protection.
For further advice contact:
Dr. J.F.H. van Hienen - general aspects of radiation protection PO Box 25, 1755 ZG Petten, Netherlands Tel +31-224564346, Fax +31-224568491 Email: vanhienen@nrg.eu
Mr Arjen D. Poley - waste management PO Box 25, 1755 ZG Petten, Netherlands Tel +31-224564333, Fax +31-224568491 Email: poley@nrg.eu
Radiation Protection Policy in the Netherlands
Workers and the general public are protected against dangers from ionising radiation by the enforcement of a system of safety standards. These ensure that exposures from 'practices' (activities using artificial radionuclides or activities in which natural radionuclides are processed because of their radioactive properties) and other 'work activities' involving exposure to radiation are so low as not to be of safety concern. The same 'Basic Safety Standards (BSS)' apply in all countries of the European Union.
The BSS document can be found as pdf-file (154 kb) on the EU-website:
http://europa.eu.int/comm/environment/radprot/legislation/9629.pdf.
The relevant Dutch regulations were revised in
September 2001 and are expected to came into force in 2002.
Refer to the Staatsblad 397:
Staatsblad 397 as pdf-file (600 kb, downloaded from: www.overheid.nl)
Staatsblad 397 as html (converted by Google to html-version)
Enforcement of the BSS is achieved by means of controls on those activities that make use of radiation. These controls apply to all activities involving the use of artificial radiation sources (practices), and to some work activities involving naturally radioactive materials - where there is the potential for significant increases in exposures of workers or the public.
Exclusion, exemption and clearance from regulatory controls
![[unscear report 2000 -sources]](../../../../images/un/unscear2000sources100.jpg)
Exposures from certain sources of natural radiation are not amenable
to control. To put this into context, average worldwide exposure
to natural radiation sources is about 2.4 mSv per year, with a
typical range between 1 mSv per year in some areas and 10 mSv per
year in others.
[See the UNSCEAR report on the UNSCEAR website :
http://www.unscear.org/reports/2000_1.html].
Of this total exposure about half is due to radon gas from the ground and
about one eight of which comes from radiation naturally present in the body.
Exposures from medical sources will typically add a further 15%,
while exposures to the general public from work activities add less
than 0.5% (5-10 microsieverts). Regulatory controls are therefore
only applied to a small proportion of the total exposure experienced
by human beings.
Natural radiation from the Earth's surface, cosmic radiation and radiation from the body are excluded from the system of radiation protection. An exception to this general principle is made for some work activities that make use of materials that are naturally radioactive but are processed for reasons other than their radioactive properties; for example potassium with the radioactive isotope potassium-40 is used to produce agricultural fertilisers. In such cases, where it is possible that workers or members of the public will experience a significant increase in radiation exposure, these work activities are subject to control.
Practices that make use of radionuclides in very small amounts are exempted from regulatory control, on the basis that the potential exposures are so low as not to be of safety concern. The concept of clearance also applies to the regulatory control of practices, in this case materials from practices already authorised may be released from regulation provided activity levels are lower than amounts specified by national authorities.
The approach being taken to clearance and exemption in the Netherlands is to establish a uniform set of radionuclide specific concentrations and total quantities that are used to establish both clearance and exemption for practices. (Work activities using natural radionuclides are discussed below.) These criteria have been developed for a wide range of individual radionuclides and apply regardless of whether the nuclide is naturally occurring or is artificially created. They are derived from the basic criteria that apply in all countries of the EU. That is, individual doses incurred by members of the public and non-radiation workers should be of the order of 10 microsieverts or less in a year, and the total (collective) dose should be less than about 1 man sievert.
Control of work activities involving use of natural radionuclides - NORM
Although the Dutch Regulations provide a unified list of clearance and exemption levels to be applied to both natural and artificial radionuclides, there are different underlying assumptions as regards exposure in the case of work activities involving use of naturally occurring radioactive materials (NORM). Here the basic objective of the system of control is to ensure that exposures are low compared with the natural background dose. The clearance/exemption levels are used to determine if the work activity should be reported to the regulatory authorities. Where the radioactivity concentrations are more than 10 times the specified levels the relevant work activity will require an authorisation from the regulatory authorities, whereas practices involving the use of artificial radionuclides require an authorisation at the specified activity levels. This difference in approach reflects the tight standards of control traditionally applied to materials being used because of their radioactive properties - though in practice the implications of any given level of exposure is the same regardless of its source.
The above issues are discussed in greater depth in the attached paper (pdf file, 103 kb), which was presented at the IAEA Conference on 'Management of Radioactive Waste from Non-Power Applications - Sharing the Experience', Malta, November, 2001.
General contact point for all services:
Dr. R. Huiskamp, NRG-RE PO Box 25, 1755 ZG Petten, Netherlands tel: +31 224 56 4234, fax: +31 224 56 8491, e-mail: re@nrg.eu