OPTIMISATION OF RADIATION PROTECTION IN NORM INDUSTRIES 3 NOVEMBER 2015 AJ VAN DER WESTHUIZEN

Transcription

1 OPTIMISATION OF RADIATION PROTECTION IN NORM INDUSTRIES 3 NOVEMBER 2015 AJ VAN DER WESTHUIZEN

2 GENERAL SAFETY REQUIREMENTS

3 GENERAL SAFETY REQUIREMENTS PART 3 (GSR PART 3) Definition of Optimisation The process of determining what level of protection and safety would result in the magnitude of individual doses, the number of individuals (workers and members of the public) subject to exposure and the likelihood of exposure being as low as reasonably achievable, economic and social factors being taken into account (ALARA) Safety Principles (Section 1.7) Principle 5 Optimisation Principle 8 Mitigate radiation accidents Principle 10 Protective actions justified and optimised. Justification Optimisation Dose Limits

4 NORM INDUSTRIES

5 Phosphate Copper Titanium Dioxide Zircon Industry TYPICAL ACTIVITY DISTRIBUTION Zircon Sand SA/Australia China Malaysia Baddeleyite Ceramic Tile glazes Zirconia Ilmenite Sand Ilmenite Rock Rutile Leucoxene TiO2 Pulp Copper concentrate Copper slag Phosphate Rock (Sed) Phosphate Rock (Ig) Phosphogypsum Fertilizer Bq/g

6 ACTIVITIES ZIRCON INDUSTRY Material Country U-238 (Bq/g) Th-232 (Bq/g) Type Sand Australia Mineral China Mineral Malaysia Mineral South Africa Mineral USA Mineral Baddeleyite Russian Federation Mineral South Africa* Mineral Fritz Product Ceramic tile glazes Product Zirconia Product * The South African Baddeleyite Production has ceased the late 90 s.

7 TYPICAL DOSE Industry Zircon Description Dose Range msv/a Mining and processing 1 5 Glaze Production Zircon in Foundries Fused Zirconia Titanium dioxide Dry Separation Plants 1 7 Phosphate Copper Ammonium Phosphate Thermal Phosphorous Mining Crushing & Milling Smelting Refining and Final Product

8 SUMMARY Significant spread in activity, depending on the ore body. o U-238 in Zircon sand from around 2-3 Bq/g in South Africa and Australia, to 62 Bq/g in Malaysia. U-238 decay series not always dominant and contribution from Th-232 cannot be ignored. Dose in general range up to 10 msv/a for primary production and less than 1 msv/a for secondary processes. o Primarily Inhalation and External Gamma Dose Fused Zirconia Production 2:1 ratio Copper Production has external gamma the more significant contributor to total dose. For Copper Production, Fused Zirconia Production and Phosphate Mining and Beneficiation, radon was found to be negligible.

9 OPTIMISATION

10 Optimisation Options Work plan and work schedule General worker education Awareness and involvement of workers Communication Job specific means Facility design Time spent Reducing the number of workers SAFETY REPORT SERIES NO 21 Reducing dose rates Time Option Suitability for NORM Combination of general labour law and resource restrictions force specific work patterns. It is necessary. Literacy levels however, a possible constraint. Suitable Suitable Reducing dose rates Shielding Specialised training Suitable Suitable for new facilities, specifically on opportunities for dust reduction. (Limited opportunity for existing facilities.) Combination of general labour law and resource restrictions force specific work patterns. Unsuitable Complex processes require a number specific, trained people for the duration of a shift. Unsuitable Complex processes require a number specific, trained people for the duration of a shift. Unsuitable Standard health and safety measures and integrated management systems not mentioned. (GSR Part 3 mentions both.)

11 FACTORS AFFECTING OPTIMISATION Optimisation Resources Systems Site specific Nature Equipment People Finance Ore body Location Type of industry Large volumes Large surface areas Generally low specific activity Homogenous distribution

12 NATURE OF THE BEAST DOSE RATE DISTRIBUTION Vermiculite Operations Average for the period Average is 0.8 nsv/h th Percentile is 1.26 nsv/h Average ( ) 1.55 nsv/h

13 SITE SPECIFIC (GSR Part 3) 1.36: Safety measures and security measures have in common the aim of protecting human life and health and the environment. (GSR Part 3) 5.10(c) The establishment of any restrictions on the use of or access to the areas concerned before, during and, if necessary, after remediation. In Practice: o Historic dumping site o 24.7 hectares o Fencing Traditional solution. Site specific constraint Elephants damage or destroy fences in search of food.

14 PRACTICAL EXAMPLES OF SYSTEM OPTIMISATION

15 FITNESS TO WORK Automatic notification to supervisor Medical Fitness to work (GSR Part 3), Programmes for workers health shall be designed to assess the initial fitness and continuing fitness of workers for their intended tasks Occupational Hygiene Program Measuring & Monitoring OMP makes informed decision Measuring & Monitoring RP Program Fit with restrictions Fit to work Unfit to work OMP discuss with individual Automatic notification to Supervisor Medical separation Alternative placement Non-attendance automatic report to Supervisor

16 INTEGRATION OF SHEQ/RP REQUIREMENTS DURING DECOMMISSIONING (GSR Part 3)5.12(d)(i) In the choice of the optimized option: Radiological impacts on people and the environment are considered together with nonradiological impacts on people and the environment and with technical, societal and economic factors. Developed a tool to evaluate decommissioning options. Consider: Legislation Technological solutions Conventional Health and Safety Environmental Impact Dose Future land use

17 INTEGRATION OF SHEQ/RP REQUIREMENTS DURING DECOMMISSIONING Description Legislation and Regulations Technology Health & Safety Conventional safety risk, after risk remediation, during execution of strategy.* Occupational exposure during execution of strategy Occupational exposure after execution of strategy No legislation required for decommissioning. Score Technology for example, methods for decontamination or capping, is generally available. Legislation applicable, but no permit required. Technology for example, methods for decontamination or capping, is can be obtained, but have extraordinary cost implication. Legislation applicable, but single permit required. Technology for example, methods for decontamination or capping, will be available in near future. (< 5Years) Legislation applicable and multiple permits required. Technology for example, methods for decontamination or capping, will be available in future. (>10 Years) Legislation prohibiting the decommissioning option. (Fatal Flaw) Not envisaged that technology will be available in the next 50 years to ensure a successful decommissioning. Low Moderate High Major Critical <1 msv/a <1 msv/a <5 msv/a >1 msv/a <5 msv/a >1 msv/a <10 msv/a >5 msv/a <10 msv/a >5 msv/a <10 msv/a >20 msv/a <10 msv/a >20 msv/a >20 msv/a (Fatal Flaw) >20 msv/a (Fatal Flaw) Total Created a decision matrix for integrated optimisation and justification for decommissioning.

18 BULK MONITORING 1m 24.7 hectares Wild animals Rough Terrain Waste site Same principles applied in the current operations. Successfully identified historic hot spots in plant area.

19 SUMMARY The principles of GSR Part 3 are sound, but implementation may face site specific constraints. It is possible to: Integrate non-radiation/radiation risks. Radiation protection does not have to be a stand-alone program Experience has shown that the current optimisation options are not as effective for NORM as for the Nuclear Reactor Industry. Physical, economical and financial differences Monitoring strategies require a different approach Dose rate for a particular sector of the process fairly consistent. Area Contamination Surveys for RP purposes of little value. Bulk sampling A standard 1 x 1 m grid sampling strategy is unnecessary with fairly homogenous activity distribution, large surface areas etc.

20 OPTIMISATION IMPACT

21 COPPER MINING AND PROCESSING

22 Dust Concentration Dose Rate UNDERGROUND OPERATIONS (AVERAGE PER YEAR) Dust Concentration (mg/m3) Dose Rate (usv/h) 0 Clear correlation between area dose rates and dust concentration.

23 nsv/h DOSE RATE DISTRIBUTION UG MINING Measurement (nsv/h) Average (nsv/h)

24 Beta Alpha CONTAMINATION (BQ/CM2) UG MINING Beta/Gamma Alpha Alpha Contamination o Average: Bq/cm2 o Standard Deviation: Bq/cm2

25 Dust Concentration Dose Rate CRUSHING AND MILLING (AVERAGE PER YEAR) Dust concentration (mg/m3) Average Dose Rate (usv/h) 0 Clear correlation between area dose rates and dust concentration.

26 Dust Concentration Dose Rate SMELTING INTERIM STEP (AVERAGE PER YEAR) Dust Concentration (mg/m3) Average Dose Rate (usv/h) Clear correlation between area dose rates and dust concentration.

27 DOSE RATE DISTRIBUTION SMELTER STEP Measurement (nsv/h) Average (nsv/h)

28 Dust Concentration Dose Rate REFINERY TANK HOUSE (AVERAGE PER YEAR) Dust Concentration (mg/m3) Average Dose Rate (usv/h) Clear correlation between area dose rates and dust concentration.

29 MINERAL SANDS

30 INDUSTRY Data representing around 95% of the mineral sands industry in Australia at the time. Activity concentrations ranged from Bq/g, Bq/g and 4-5 Bq/g High activity material only processed in 1 plant and only in this plan has the dose exceed 5 msv/a. Dose in this plant exceeded 10 msv/a Was during a period of re-processing Activity concentrations in the order of 8 9 Bq/g Excessive dust levels.

31 MONITORING STRATEGY No explanation in the report as to why the numbers were decreasing, but a possibility is that the focus was more on workers where the dose has a potential of exceeding 5 msv/a.

32 TYPICAL DOSE DISTRIBUTION Average less than 5 msv/a, but can exceed 10 msv/a. Initially incorrect dose conversion factors used. Abnormal conditions caused significant increase in exposure.

33 SUMMARY Mineral Sands Industries in Australia and Copper-, Phosphateand Zirconia Industries in South Africa considers External Dose and Inhalation Dose for Dose Assessments. Strong correlation between dose rate and dust concentrations. Unlikely to have significant hot-spots after mining contamination surveys found to contribute very little for RP purposes.

34 MANAGEMENT SYSTEMS AND OPTIMISATION

35 WHY THE FOCUS? GSR Part 3: Requirement 5 The principal parties shall ensure that protection and safety of are effectively integrated into the overall management system of the organization for which they are responsible. Experience has shown that traditional health, safety and environmental management practices in most cases adequately address radiation protection optimisation needs. A universally acceptable approach is to follow a recognised management system. More should be done to align and strengthen the radiation protection management system as this will contribute to optimisation in NORM industries.

36 COMPARISON WITH ISO SYSTEMS ISO9001:2015 ISO 14001:2015 ISO Planned Standard GS-R-3 1. Scope 1. Scope 1. Scope 3. Terms and definitions 3. Terms and definitions 3. Terms and definitions 4. Context of the organisation 4.1 Understanding the organization and its context. 4. Context of the organisation 4.1 Understanding the organization and its context. 4. Context of the organisation 4.1 Understanding the organization and its context General Requirements 2.5 Safety Culture 2.3 General Requirements 4.2 Understanding the needs and expectations of interested parties. 4.2 Understanding the needs and expectations of interested parties. 4.2 Understanding the needs and expectations of interested parties. 3.6 Satisfaction of Interested Parties 4.4 Quality management system and its processes 5.1 Leadership and commitment 4.4 Environmental management system 4.4 OH&S management system. 5.1 Leadership and commitment 5.1 Leadership and commitment Developing processes Process management Management commitment 5.2 Quality policy 5.2 Environmental policy 5.2 Policy 3.7 Organisational Policy 5.3 Organisational roles, responsibilities and authorities 5.3 Organisational roles, responsibilities and authorities 5.3 Organisational roles, responsibilities and authorities Management commitment Responsibility and authority for the management system

37 COMPARISON WITH ISO SYSTEMS ISO9001:2015 ISO 14001:2015 ISO Planned Standard GS-R Planning 6. Planning for the QMS 6. Planning 6. Planning 6.2 Quality objectives and planning to achieve them Significant environmental aspects Compliance obligations Risk associated with threats and opportunities 6.2 Environmental objectives and planning to achieve them Hazard identification Determination of legal and other requirements Assessment of OH&S risks Planning for changes 6.2 OH&S objectives and planning to achieve them. 6.3 Planning of changes 8.2 Management of change 5.4 Developing processes 2.3 General requirements Managing organisational change Planning Managing organisational change 7. Support 7. Support 7. Support 7.1 Resources 7.1 Resources 7.1 Resources General Provision of resources People Human resources Infrastructure 4.5 Infrastructure and the working environment

38 COMPARISON WITH ISO SYSTEMS ISO9001:2015 ISO 14001:2015 ISO Planned Standard GS-R Competence 7.2 Competence 7.2 Competence Human resources 7.3 Awareness 7.3 Awareness 7.3 Awareness 4.3 Human resources 7.4 Communication 7.4 Communication 7.4 Communication Communication 7.5 Documented information General Control of documented information 8. Operation 8.1 Operational planning and control 8.2 Determination of requirements for products and services 8.3 Design and development of products 8.4 Control of externally provided products and services 8.5 Production and service provision 7.5 Documented information General Control of documented information 8. Operation 8.1 Operational planning and control 7.5 Documented information General Control of documented information 8. Operation 8.1 Operational planning and control Hierarchy of control. 8.4 Procurement 8.5 Contractors Control of changes 8.2 Management of change Documentation of the management system Control of documents Control of records Grading the application of management system requirements Grading the application of management system requirements 5.2 Developing processes Developing processes Process management Control of products Purchasing Managing organisational change

39 COMPARISON WITH ISO SYSTEMS ISO9001:2015 ISO 14001:2015 ISO Planned Standard GS-R-3 9. Performance evaluation 9.1 Monitoring, measurement, analysis and evaluation 9. Performance evaluation 9.1 Monitoring, measurement, analysis and evaluation 9. Performance evaluation 9.1 Monitoring, measurement, analysis and evaluation 6.1 Monitoring and measurement Independent assessment Customer satisfaction 3.6 Satisfaction of Interested Parties Analysis and evaluation Evaluation of compliance Evaluation of compliance 6.2 Self assessment 9.2 Internal Audit 9.2 Internal Audit 9.2 Internal Audit 6.2 Self assessment 9.3 Management review 9.3 Management review 9.3 Management review Management review 10. Improvement 10.2 Nonconformity and corrective action 10. Improvement 10.1 Nonconformity and corrective action 10. Improvement 10.1 Nonconformity and corrective action Non conformities, corrective and preventative action 10.3 Continual improvement 10.2 Continual improvement 10.2 Continual improvement Improvement 8.6 Emergency preparedness and response

40 CURRENT SYSTEM PERCEIVED WEAKNESSES IAEA Safety Standards Series No. GS-R-3: The Management System for Facilities and Activities. Requirement 13 Risk Assessment (GSR Part 3) Current radiation protection management system does not specifically address risk assessment, yet it is the cornerstone of radiation protection and optimisation. Requirement 15 and 43 Emergency situations. (GSR Part 3) Future ISO45001 (OSHAS 18001) covers emergency preparedness and response. Current radiation protection management system does not specifically address emergency situations, yet GSR Part 3 dedicate a chapter to it.

41 PRACTICAL ALIGNMENT Authorisation Conditions from National Nuclear Regulator. Company has integrated Management System for Health, Safety, Environment, Security, HR. Company also certified ISO9001 and ISO14001 A single procedure created to align NNR documentation with Integrated Management System. Bulk of the radiation protection system can be audited. International Standards Organisation has aligned its systems. NO REASON WHY RADIATION PROTECTION MANAGEMENT SYSTEM CANNOT BE ALIGNED WITH ISO PHILOSOPHY AND BECOME AN ISO SYSTEM.

42 FOR CONSIDERATION

43 DEFINITION OF OPTIMISATION The process of determining what level of protection and safety would result in the magnitude of individual doses, the number of individuals (workers and members of the public) subject to exposure and the likelihood of exposure being as low as reasonably achievable, economic and social factors being taken into account There are a number of system requirements in GSR Part 3, for example: Requirement 14: Monitoring for verification of compliance. Requirement 25: Assessment of occupational exposure and workers health surveillance. Should the definition not include reference to system optimisation as well?

44 GRADED APPROACH FOR AREA CLASSIFICATION Yes 90 th Percentile < 1 msv/a No Average, 95 th percentile or Maximum? Graded approach Is a combination perhaps a solution? Exempted Average < 1 ms/a Yes No Exempted (Bi-annual surveys) Yes 90 th Percentile < 5 msv/a No Supervised (Bi-annual surveys) Yes Average < 5 msv/a No (GSR Part 3) 3.6.: The application of the requirements of these Standards shall be in accordance with the graded approach and shall also conform to any requirements specified by the regulatory body. Supervised (Quarterly surveys) Controlled (Quarterly surveys)

45 PLANNED VS. EXISTING SITUATIONS 1.20(a) A planned exposure situation is a situation of exposure that arises from the planned operation of a source or from a planned activity that results in an exposure due to a source. 1.20(c) An existing exposure situation is a situation of exposure that already exists when a decision on the need for control needs to be taken Day-to-day management generally as Planned Exposure Situations Nevertheless, sites usually have elements of Existing Exposure Situations Old Process Facility, often near the end of life where refurbishment is not justified financially. Historic Waste Dumps Complex situations may exists: Reprocessing of an old Tailings Dam Personal View: Day-to-day management must be dealt with as a Planned Exposure situation while facility is in operation. License holders to motivate and apply for a portion of an operation to be declared an Existing Exposure Situation Need to create a decision framework to guide regulators and authorisation holders. To include in authorisation conditions to ensure legal status.

46 OTHER MATTERS Is a single radiation protection standard for NORM, Medical Exposure and Nuclear Reactors the right approach? Is the standard optimisation options suitable for NORM? (Revision of Safety Reports Series 21: Optimization of Radiation Protection in the Control of Occupational Exposure) Is it not time for an ISO system for radiation management? System component System specialist/radiation specialist Technical component Radiation specialist Regulators and Authorisation Holders remains responsible, but a third party is introduced to evaluate performance/compliance, thus creating an additional level of verification and optimisation.

47 My recognition and thanks to Nick Tsurikov, Shane Motlaloga and Trevor Boal for their input and contributions.