1. Application of the International Safety Standards to Radon and NORM
Denis Wymer, IAEA
Shengli Niu, ILO

2. International Safety Standards
Promoting international harmonization of radiation protection and safety
IAEA Statute – establish Safety Standards and provide for their application
In consultation/collaboration with competent organs of the UN and the specialized agencies concerned (e.g. ILO, WHO, FAO etc.)
International consensus

3. International Safety Standards
Safety Fundamentals
Safety Requirements
Safety Guides

4. Safety Guides: Occupational exposure to Rn & NORM

5. Documents supporting the Standards – Safety Reports

6. Other Safety Reports in preparation
General:
“Assessing the need for radiation protection measures in work involving minerals and raw materials”
Practice-specific:
Phosphates
Zircon
TiO2
Industrial uses of thorium
Monazite and rare earths
Production of metals
Coal & coal ash
Aim to publish in 2006

7. IAEA Safety Glossary – definition of “NORM”
“Radioactive material containing no significant amounts of radionuclides other than naturally occurring radionuclides”
Radioactive material = material designated in national law or by a regulatory body as being subject to regulatory control because of its radioactivity
Note: TENORM is not in the Safety Glossary and its use is discouraged:
It does not serve any useful purpose for radiation protection -- some material in its natural state is more radiologically hazardous than some “technologically enhanced” material
The real issue is whether the material is classified as radioactive (i.e. whether it needs to be controlled)

8. Application of the Standards – (1) Radon
Normally considered as chronic exposure subject to intervention
Optimization of protection -- optimized action level for intervention through remedial action
Guideline action level 1000 Bq/m3 for workplaces
No action required below action level
If remedial action cannot reasonably achieve reduction to below action level, apply requirements for practices (usually an issue only in underground workplaces)

9. Application of the standards – (2) NORM
As with radon – optimization of protection
Usually unnecessary to regulate material below:
1 Bq/g (U, Th series radionuclides)
10 Bq/g (K-40)
irrespective of quantity, or whether natural or processed
Building materials below these levels may require consideration – separate guidance being developed
Does not apply to Rn in air, drinking water, foodstuffs, residues in environment, transport
Can also be used as clearance levels

10. What happens if the levels for Rn (after attempted remediation) and/or NORM are exceeded?
Again – optimization of protection
Graded approach to regulation
Consider existing OHS and environmental controls
Then select appropriate regulatory approach
Decide not to apply regulatory requirements (for instance, by exempting the practice or source)
Notification alone
Notification + registration
Notification + licensing

11. (1). Guideline criteria for deciding not to apply
(1) Guideline criteria for deciding not to apply requirements (gamma and dust)
Guideline level for occupational exposure – 1 to 2 mSv/a (Safety Guide RS-G-1.1, based on ICRP 75)
Safety Guide RS-G-1.7: materials for which regulation is usually unnecessary on the basis of activity concentration are unlikely to give rise to worker or public doses >1 mSv/a
Experience (see, for instance, UNSCEAR 2000): doses to public << doses to workers, especially if wastes subject to normal industrial controls
Therefore, we can use occupational guideline level of mSv/a, in the knowledge that, below this level, doses to public will be <<1 mSv/a

12. (2) Guideline criteria for “notification alone”
International Basic Safety Standards (BSS) – notification alone could be sufficient where exposures are unlikely to exceed a small fraction of the relevant limits
Useful where regulatory body simply needs to be kept informed

13. (3) Guideline criteria for “notification + registration”
Appropriate for many types of activity involving exposure to radon and/or NORM
Most of such operations by their nature cannot give rise to extreme exposure scenarios
Some OHS and environmental controls already likely to be in place
Minimal additional requirements may be needed for radiological purposes, e.g. monitoring, good work practices – basic ALARA considerations

14. (4) Guideline criteria for “notification + licensing”
The highest level in the graded approach
Appropriate only where specific measures needed to control the actions of workers, formalized procedures to keep within dose limits and maintain doses ALARA
Likely to be needed only in certain operations, e.g. involving significant quantities of material with very high activity concentrations

15. Future development of the Standards
The BSS are now nearly 10 years old
At the time of publication of the BSS, explicit ICRP recommendations on natural sources existed only for radon
Additional standards material has since been included in various Safety Guides
BSS now starting to be reviewed

16. Review of standards: Issues for natural sources
Possible need for some clarification and consolidation, but otherwise relatively few issues have been raised
Some gaps, e.g. cosmic radiation, building materials
Existing exemption levels are based on doses of the order of 10 μSv/a – not applicable to NORM
The radon action level does not apply to uranium mining, but uranium ore is just one type of NORM – why should we have different standards for the nuclear fuel cycle?

17. The standards are in place
The standards are in place. So …… what are the implications for industrial processes?
Activity concentrations and doses:
Facility-specific measured data are becoming more plentiful
Many previously-modelled worker doses are gross overestimates
IAEA Safety Reports will include new, previously unpublished data based on facility-specific measurements and dosimetry
The list of materials >1 Bq/g (U, Th series) is not that large (44)
The list of processes giving rise to worker doses from gamma and dust >1-2 mSv/a, or to Rn >1000 Bq/m3, is even smaller (9)
Non-excluded exposures to K-rich materials can be disregarded – doses always <1 mSv/a, irrespective of K-40 concentration

18. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (1) raw materials
Material
Typical activity conc. (Bq/g)
Monazite sand
40 to Th+
Metal ores e.g. Nb/Ta, Cu
Up to U+, 232Th+
Zircon sand
1 to 4 232U+
Phosphate rock
0.03 to U+
Feedstocks, TiO2 production
0.001 to U, 226Ra
Bauxite
0.035 to Th+

19. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (2) bulk residues
Material
Typical activity conc. (Bq/g)
Niobium slag
20 to Th
Tin slag
0.07 to Th
Phosphogypsum, HCl process
2 to Ra
Red mud, alumina production
0.1 to 3 232U, 232Th
Phosphogypsum, H2SO4 process
0.015 to Ra
Copper slag
0.4 to Ra
Phosphorus slag
0.3 to 2 238U

20. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (3) scales
Material
Typical activity conc. (Bq/g)
Oil & gas production scale
0.1 to Ra
Phosphoric acid wet process scale
0.003 to Ra
TiO2 pigment production scale
<1 to Ra, 226Ra
Rare earth extraction scale
Ra, 228Th
Scale, mines with Ra-rich water
Up to Ra, 228Ra
Iron smelting scale
Up to Pb, 210Po
Coal combustion scale
> Pb

21. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (4) sludges, sediments
Material
Typical activity conc. (Bq/g)
Rare earth extraction residue
23 to Ra
Oil and gas production sludge
0.05 to Ra
Niobium extraction precipitate Ra
Iron smelting sludge
12 to Pb
TiO2 pigment production residue
<1 to Th, 228Ra
Water treatment sludge
0.1 to Ra

22. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (5) precipitator dust
Material
Typical activity conc. (Bq/g)
Elemental phosphorus furnace dust Pb
Fused zirconia furnace dust Po
Niobium extraction furnace dust
100 to Pb, 210Po
Metal smelting furnace dust
Up to Pb, 210Po

23. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (6) intermediate products
Material
Typical activity conc. (Bq/g)
Thorium compounds
Up to Th
Thorium concentrate
Up to Th
Pyrochlore concentrate
80 232Th
Cerium concentrate
10 232Th
Fused zirconia
2.1 to U

24. Typical activity conc. (Bq/g)
NORM needing regulatory consideration on the basis of activity concentration – (7) products
Material
Typical activity conc. (Bq/g)
Gas mantles
500 to Th
Thoriated glass
200 to Th
Th-containing polishing powders Th
Thoriated welding electrodes
30 to Th
Thorium alloys
46 to Th
Zircon refractories U
Phosphate fertilizers
0.4 to U
Technical grade phosphoric acid
0.14 to 2 238U
Phosphogypsum plasterboard
0.004 to Ra

25. Type of operation Worker dose (mSv/a)
Types of operation identified as requiring regulation on the basis of gamma/dust worker doses >1-2 mSv/a or Rn >1000 Bq/m3
Type of operation
Worker dose (mSv/a)
Rare earth extraction
Approaching (exceeding?) dose limit
Production of thorium compounds
Typically 6 to 15
Th-containing product manufacture
Processing Nb/Ta ore
Doses can vary from <1 up to a
Some underground mines
significant fraction of dose limit
Scale removal, oil & gas
Scale removal, TiO2 pigment prod.
<1 to 6
Thermal phosphorus production
0.2 to 5
Fused zirconia production
0.25 to 3

26. To summarize ……………
The international standards provide the necessary requirements and guidance for protection of workers against radon and NORM
No major changes in standards anticipated
Supporting material (Safety Reports), much of it practice-specific, is being developed in order to assist in the application of the standards
(cont’d)………………..

27. cont’d …………….
The standards provide clear criteria for identifying what can be disregarded from a regulatory point of view – these criteria are expressed in terms of activity concentrations
The standards provide for a graded approach to regulation, consistent with the optimization of protection
Important to take into account existing OHS and environmental controls – these may provide sufficient protection against radiological hazards
(cont’d)…………………….

28. cont’d……………
One option in the graded approach is a decision not to apply regulatory requirements
Guideline criterion for gamma and dust exposure is a worker dose of 1-2 mSv/a – corresponding doses to the public are likely to be <<1 mSv/a
Therefore, availability of reliable information on worker doses is important
Studies based heavily on modelling can be misleading -- tend to overestimate worker doses
(cont’d)……………………..

29. Possibility of doses >>1-2 mSv/a:
cont’d…………………
Possibility of doses >>1-2 mSv/a:
Rare earths extraction
Manufacture of Th compounds & Th-containing products
Nb/Ta ore processing
Some underground mines (Rn exposure)
Some scale removal operations (e.g. oil & gas industry)
Possibility of doses moderately >1-2 mSv/a:
Some underground mines
Some scale removal operations (e.g. TiO2 production)
Fume & precipitator dust (phosphorus, ZrO2 production)
This is not a very long list !

30. To conclude………………. The so-called “NORM problem” is not a problem
We have the necessary standards – an optimized approach to defining:
the scope of regulation
the degree of regulation
Existing OHS and environmental controls must be taken into account
We know what we are up against – on the basis of international standards, the number of industrial processes requiring specific radiological controls is not that great !