1. The New ICRP Recommendations Essen, 15 March 2006
5th ISOE European Workshop on
Occupational Exposure Management at Nuclear Facilities
The New ICRP Recommendations Essen, 15 March 2006
Lars-Erik Holm

2. ICRP’s 2006 Recommendations
Volume 36, Issue 4, 2006
Aims and scope  
Biological aspects
Dosimetric quantities
The system of radiological protection
Medical exposures
Natural exposures
Potential exposures
Emergency situations
The scope of regulating radiological protection
Protection of the environment
Implementation of the Commission’s recommendations
The radiological protection paradigm
Glossary
References
Recommendations of the International Commission on Radiological Protection, 2006

3. More Continuity than Change in
the 2006 Recommendations
Most recommendations will remain - because they work
and are clear
… and some things are to
Be explained - because more guidance is needed
Be added - because there has been a void
Differ - because understanding has evolved

4. Major Features I
Maintaining the 3 principles of radiological protection, and clarifying how they apply to sources and the individual;
Updating the radiation and tissue weighting factors;
Maintaining the dose limits that represent the most that will be accepted in planned situations by regulatory authorities;
Using the concept of constraints in the source-related protection to all situations. The constraints quantify the most fundamental levels of protection for workers and the public from single sources;

5. Major Features II
Replacing ’practices’ and ’interventions’ with 3 types of exposure situations which address all conceivable circumstances:
- planned situations;
- emergency situations; and
- existing exposure situations.
Including a policy for protection of the environment.

6. The Aim of the Recommendations
To provide an appropriate standard of protection for people and the environment, without unduly limiting the beneficial actions giving rise to radiation exposure.
* * * *
The new recommendations consolidate and add to previous recommendations issued in various ICRP publications.
The existing numerical recommendations in the policy guidance given since 1991 remain valid unless otherwise stated.

7. Building Blocks
C1: Low-Dose Extrapolation of Radiation-Related Cancer Risk
C1: Biological and Epidemiological Information on Health Risks Attributable to Ionising Radiation
C2: Dosimetric Quantities Used in Radiological Protection
C3: Radiological Protection in Medicine
C4: Optimisation of Protection
C4: Assessing Dose to the Representative Individual
MC: The Scope of Radiological Protection Regulations
MC: The Radiological Protection Paradigm

8. Radiation Weighting Factors, wR
Type and energy range
Publication 60
2006
Photons, all energies 1
Electrons and muons, all energies
Protons 5 2
Alpha particles 20
Neutrons
Stepwise function
Continuous function

9. New Reference Phantoms
MIRD Phantom
Voxel Male and Female Phantoms

10. Main Conclusions on Biology
Dose-response for cancer and hereditary effects: A simple proportionate relationship at low doses between dose and risk.
DDREF: Retain a value of 2.
Nominal probability coefficients for cancer: Sv-1 for whole population and Sv-1 for adult workers.
Nominal probability coefficients for heritable diseases: Up to 2nd generation: Sv-1 for whole population and Sv-1 for adult workers.
Risks of non-cancer diseases: Great uncertainty on dose response < 1 Sv; no judgement on low dose risk possible.

11. Tissue Weighting Factors, wT
Bone-marrow, breast, colon, lung, stomach, remainder tissues1
0.12
0.72
Gonads
0.08
Bladder, oesophagus, liver, thyroid
0.04
0.16
Bone surface, brain, salivary glands, skin
0.01
1 Nominal wT divided equally between 14 tissues.

12. NOMINAL RISK COEFFICIENTS FOR STOCHASTIC EFFECTS (% Sv-1)
Exposed population
Cancer
Heritable effects
Total
ICRP60
2006
Whole
6.0
5.5
1.3
0.2
7.3
5.7
Adult
4.8
4.1
0.8
0.1
5.6
4.2

13. Principles of Protection FOR SINGLE SOURCES
JUSTIFICATION
Any decision that alters the existing radiation exposure situation, e.g., by introducing a new radiation source or by reducing existing exposure, should do more good than harm.

14. Principles of Protection FOR SINGLE SOURCES
OPTIMISATION
Optimisation of protection should ensure the selection of the best protection option under the prevailing circumstances, and maximising the margin of good over harm. This procedure should be constrained by restrictions on the doses or risks to individuals (dose or risk constraints).
Optimisation involves keeping exposures as low as reasonably achievable, taking into account economic and social factors, as well as any inequity in the distribution of doses and benefits amongst those exposed.

15. Principles of Protection FOR INDIVIDUALS
DOSE LIMITS
In planned situations, the total dose to any individual from all the regulated sources should not exceed the appropriate dose limits specified by the Commission.

16. Restrictions and Reference Levels in Publication 60
Dose limit
Dose constraint
Reference levels
Recording level
Investigation level
Intervention level
Action level
Diagnostic reference level

17. Dose Constraint 2006 (I)
It is the most fundamental level of protection for the most exposed individuals from a single source within a class of exposure.
It applies to all situations;
It is used prospectively as the starting point of the optimisation process;
It is not a form of retrospective dose limitation.

18. Dose Constraint 2006 (II)
In planned situations, it is less than limits;
In emergency or existing exposure situations, it represents the level of dose/risk where action is almost always warranted;
The chosen value will depend upon the circumstances of the exposure;
It will be established at the national or local level by regulators or operators.

19. Dose Constraint 2006 (III)
The numerical criteria recommended by the Commission in Publication 60 and thereafter can all be regarded as constraints.
The values fall into three defined bands: mSv, 1-20 mSv and mSv.
These bands will enable selection of an appropriate value for a constraint for a specific situation that has not been addressed explicitly by the Commission.

20. ICRP’s Band of Constraints from Single Dominant Sources
BANDS OF PROJECTED DOSE
REQUIREMENTS
mSv
Benefit on a case-by-case basis. Information, training and individual monitoring of workers, assessment of public doses.
mSv
Individual direct or indirect benefit. Information, training and either individual monitoring or assessment.
mSv
Societal benefit (not individual).
No information, training or individual monitoring. Assessment of doses for compliance.

21. Additional Radiation Dose and Risk THE CASE FOR PLANNED SITUATIONS
UNACCEPTABLE RISK
DOSE LIMIT
TOLERABLE RISK
DOSE CONSTRAINT
ACCEPTABLE RISK
OPTIMISATION
TRIVIAL RISK

22. Constraints for Radon
ICRP’s policy is based upon setting a level of effective dose from radon where action would be warranted:
10 mSv per year
ICRP’s constraints are set where action is almost always warranted:
Home Bq m-3
Work Bq m-3
National regulators apply the optimisation of protection to arrive at the level at which to act.

23. Diagnostic Reference Level
The diagnostic reference level has as its objective the optimization of protection.
The dose to the patient from a specified diagnostic procedure should not normally exceed the diagnostic reference level for that procedure.
It does not relate to individual patients.
Conceptually, the diagnostic reference level serves as a kind of constraint for a specified examination/ procedure.

24. Exclusion from Legislation
ICRP TG recommends to exclude radiation exposure situations that cannot reasonably be considered amenable as to control:
Cosmic radiation at ground level;
Radionuclides of natural origin in the human body;
Radon in ambient air: < 100 (or 40) Bq/m3; and
Any other exposure situation that the legislator judge to be unamenable to control.

25. Exclusion or Exemption
ICRP TG recommends levels for exclusion or generic exemption for:
Artificial radionuclides:
< 1 Bq/kg for alpha emitters
< 10 Bq/kg for beta/gamma emitters;
Natural radionuclides in materials, except building materials:
< 1000 Bq/kg for the head of the 238U and 232Th;
< Bq/kg for 40K
Building materials: may warrant a more restrictive consideration of the sum of 238U, 232Th and 40K, and the radiological implications should be carefully analyzed.

26. Exemption An important component of regulatory functions.
The principles for exempting a practice or a source within a practice:
individual risks must be sufficiently low as not to warrant regulatory concern (0.01 mSv a-1);
radiological protection, including the efforts of regulatory control, must be optimised; and
the practice must be justified and its sources should be inherently safe.

27. Recommended Exemption
Devices emitting adventitious radiation of max. 5 keV and max. 1 Sv h-1 at 0.1 m from any surface of the device;
Radionuclides in activity concentrations smaller than those specified by FAO and WHO for foodstuff and drinking water, and by the IAEA for non-edible commodities, for radiation sources and for materials in transport.

28. Time Schedule
March 2006: Main Commission to discuss new draft recommendations
may 2006: New international consultation of draft recommendations
November 2006: Main Commission to discuss revised draft recommendations
December 2006: Earliest possible date of ICRP adoption