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Contents 1. Introduction 2. Investigation Status of NORM

RADIATION PROTECTION STATUS AND TREND FOR THE NATURAL OCCURRING RADIOACTIVE MATERIAL (NORM) IN TAIWAN. Contents 1. Introduction 2. Investigation Status of NORM 3. Related Regulations of NORM  4. International Radiation Protection And

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Contents 1. Introduction 2. Investigation Status of NORM

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  1. RADIATION PROTECTION STATUS AND TREND FOR THE NATURAL OCCURRING RADIOACTIVEMATERIAL (NORM) IN TAIWAN Contents 1. Introduction 2. Investigation Status of NORM 3. Related Regulations of NORM  4. International Radiation Protection And Control Trend for NORM  5. Conclusions           Wang Tzu-Wen        Institute of Nuclear Energy Research, AEC Workshop on the Future Trend of Radiation Protection October 18~19, 2004

  2. 1. Introduction ● NORM or TENORM have the potential to cause elevated exposure to radiation. ● The public may not have awareness of TENORM and need information about them. ● The industries that generate these materials may need additional guidance to help manage and dispose of TENORM in ways that protect public and the environment and are economically sound.

  3. Occupational Radiation Exposures referred from UNSCEAR 2000 Report

  4. 2. Investigation Status of NORM A. The range of activity concentrations of radionuclides in different TENORM wastes generated by many industries had been investigated in Taiwan. The annual productions of wastes were also estimated. The industries investigated include: electricity production, metal foundries, building materials, ceramics, water treatment, titanium dioxide manufacturing, and fertilizer production, etc.

  5. 2. Investigation Status of NORM B. For the purpose of radiation protection to the environment and workers, a program is carrying out to investigate the significant exposure resulted from TENORM in Taiwan. The strategies of the program include: a. collecting and reviewing the international NORM activities and the associated radiological data. b. investigating the type of industries, the industrial processes, the activity concentrations in products, residues and waste and the exposure of workers and the public. c. screening the industries or the NORM activities that are excluded or exempted to regulatory controlbased on the volume, activity concentrations, chemical and physical characteristics. d. developing the assessment models of internal and external radiation doses. e. preparing the regulation or guidance based on the radiation exposure levels.

  6. 3. Related Regulations of NORM A. Ionizing Radiation Protection Act (Promulgated on Jan. 30,2002 by President) Article 4 Exceptions for Natural Radiation The provisions of the ACT do not apply to naturally occurring radioactive material, background radiation, and their exposure herein. Provided there is a threat to public safety, the Competent Authority may take them under its jurisdiction by the procedure of announcement and the regulations shall be laid down by the Competent Authority. B. Standard of Radiation Limitations in Commodities (Promulgated on Dec. 4, 2002 by AEC) In drink water, the limitations are: gross alpha: 550Bq/m3; U: 1,100Bq/m3, 226Ra and 228Ra:740Bq/m3. When the concentration of gross alpha exceeds 200Bq/m3, the radioanalysis of U, 226Ra, and 228Ra shall be performed.

  7. 3. Related Regulations of NORM C. Standard of Exemption Control of Radiation Sources (Promulgated on Jan. 29, 2003 by AEC) This Standard specify the exemption levels of radionuclides in terms of activity concentration and total activity that are referred from IAEA BSS report. The exemption levels are based on an individual dose criterion of the order of 10μSv/y and a collective dose criterion of about 1 manSv/y. D. Synopsis of the Restrictions of Radioactivity Contents in Drinking Water (Promulgated on Jan. 19, 1999 by AEC) The restrictions of radioactivity contents in drinking water are: The maximum concentration of gross alpha is 550Bq/m3. When the concentration of gross alpha exceeds 200Bq/m3, the analysis of 226Ra and 228Ra shall be performed. The maximum mixed concentration of 226Ra, and 228Ra is 200Bq/m3.

  8. 3. Related Regulations of NORM E. Synopsis of the Disposal for Abnormal Radiation Road (Promulgated on Apr. 20, 1999 by AEC) a. Annual Effective Dose≦1mSv, No Action required. b. Annual Effective Dose＞1mSv and≦5mSv, the disposal methods depend on the decision of related Competent Authority. c.Annual Effective Dose＞5mSv, the construction material shall be removed. .

  9. 3. Related Regulations of NORM F. Synopsis of the Radioactivity Restrictions in Industrial Waste As to Construction Material (Promulgated on Jan. 10, 2000 by AEC) a. Used to building, The restriction criteria of specific activities of 226Ra, 232Th and 40K are 370, 259, and 4810 Bq/kg respectively. b. Used to road, bridge, their specific activities are double of used to building. c. Used to airport runway, their specific activities are fivefold of used to building. d. Used to other facilities, a special apply to AEC for allowance.

  10. 4. International Radiation Protection And Control Trend for NORM ● The radiological consequence of NORM is a world-wide cognition of the issue involved. ●Exposure to natural source shall be considered as a chronic exposure and shall be subjected to the requirement for intervention. ● For occupational exposure, if specified by a regulatory, the exposure shall be the requirement for practice. ● The criteria for practices are based on the concepts of exclusion, exemption, and clearance. Action levels are criteria that can be used in intervetion.

  11. 4. International Radiation Protection And Control Trend for NORM A. Exclusion a. In BSS, ICRP-60, and Euratom Directive, exclusion related to the amenability of exposure to control rather than to the actual magnitude of exposures. b. Euratom Directive specifies that work activities lead to a significant exposure of workers or the public which can not be disregarded from radiation protection . B. Exemption a. ICRP-60 referred to a second basis for exemption “no reasonable control procedures can achieve significant reductions in individual and collective doses” more appropriate for NORM activities. b. EC used a dose level of 0.3mSv/y as a basis to derive exemption levels. c. In BSS and ICRP, the upper dose level to consider as a base for exemption should be 1mSv/y.

  12. 4. International Radiation Protection And Control Trend for NORM C. Clearance a. When setting exemption levels, setting clearance levels is necessary. b. Exemption and Clearance levels set the same values are reasonable. c. International agreement about harmonization of clearance levels is very important.. D. Action Levels a. In BSS, the action level for radon in workplaces is 1000Bq/m3. b. ICRP-65 recommended the action level for radon in workplaces in the range 500~1500Bq/m3. c. ICRP-82: An existing annual dose approaching about 10mSv may be used as a generic reference level below which intervention is not likely to be justifiable for some prolonged exposure situations.

  13. 5. Conclusions Most national and international radiological protection associations have reached an agreement on how to manage and control NORM and TENORM. The influence caused by natural redionuclide is becoming a well-concerned issue these days. One of AEC’s goals is to ensure the radiation safety of workers and the public. Therefore, AEC has been actively promoting the education of radiation safety to the public, so that the public can have proper awareness of radiation protection. Currently the management forward NORM and TENORM- related industries is different from the artificial sources related ones. It is important to adapt a most appropriate managing strategy which can cast minimum impact on the industries without lowering the criteria of artificial radiation related management.

  14. Thank You for Your Attention

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