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Regulations and Regulatory Issues |
Regulation, Control, and Management of
TENORM
Introduction
In the past, NORM and TENORM has been defined by what is not more than by what it is. A similar quandary exists with regulations of NORM and TENORM. Many
States believe NORM and TENORM are regulated under their general regulations on radiation, other States have specific regulations, mostly to address oil field wastes.
Internationally, regulations for TENORM are being adopted in various levels. Several regulatory initiatives are being undertaken in the
United States with respect to diffuse sources of TENORM.
Note: This section is pretty outdated. It is under revision, but may take some time to get it caught up. For informational purposes only, check with your local regulatory authority!
The Health Physics Society / American National Standards Institute (ANSI) (HPS 2009) have issued Standard N13.53, Control and Release of Technologically Enhanced Naturally Radioactive Material. The Conference of Radiation Control Program Directors (CRCPD) developed suggested regulations for States to use when developing their rules (CRCPD 2004). The new CRCPD Standard was approved by the CRCPD in 2004.
(CRCPD 2004).
The Environmental Protection Agency (EPA) had proposed changes to the RPG (EPA 1994), which would impact TENORM regulations. The proposed RPG
would have adopted the recommendations of ICRP 60 (ICRP 1990), and would recommend regulation of sources as well as limits to individuals.
However, after going nowhere for six years because of partisan wrangling at the
behest of numerous lobbies, the proposed rule was withdrawn, and a new
effort has begun to re-craft a new proposed RPG. The USNRC has a policy on alternate feedstocks and disposal of waste in 11 (e)2 uranium mill tailings disposal sites (USNRC 1995). The NRC also promulgated a final rule for license termination at uranium recovery facilities (FR June 11, 1999).
Canada is considering adopting regulations for handling of NORM based on a
previous Canadian guidance document (WCNC 1995). It uses a graded approach to the amount of protection workers would need based on expected exposure (FPTRPC 1999).
Initiatives are also being undertaken in Europe to harmonize its regulations for radioactive materials (including NORM) as part of the
European Commission efforts (EURATOM 1996). EU countries were supposed to adopt the basic recommendations as of May 2000 in their respective countries' regulations. The EU recommendations are risk-based, and use ICRP 60 as their basis.
There is concern about the risks of low level radiation growing from all sides of the issue. Industry and professional organizations are openly challenging the validity of the Linear No Threshold Hypothesis (LNT) as being too conservative and costly. Others are pointing to data showing that one alpha particle can cause cancer, and thus radioactive materials and radiation need to be regulated more vigorously than ever.
This is a serious issue. There are implications for everyone. If low levels of radiation turn out to have a threshold below where there really is no
risk to speak of, then laws may be loosened. Governments and business are already trying to figure out what to do with millions of tons of radioactive scrap metal left over from the Cold War and from the decommissioning of nuclear power plants that is now underway, as well as TENORM-contaminated scrap metal from industries like oil and gas drilling and refining. Mining companies all over the world generate billions of tons a year of tailings that are often contaminated with TENORM. Some of these tailings are regulated already for their heavy metal content, or for the chemical residues left over from processing the ores. Mine tailings disposal is a huge and costly problem. Industry representatives make up a large portion of the task forces and committees that are drafting these regulations.
If low levels of radiation actually are proven to be carcinogenic, or have
mutagenic, teratogenic, or some other detrimental effects, then current regulatory efforts may fall short of protecting the public and workers.
There is growing concern from the environmental community and the public in general that these regulations will not be protective of human health and the environment, but rather:
- Legalize trade of radioactive scrap metal for recycling into products,
- Exempt industries that release millions of tons of radioactive tailings annually into the environment,
- Allow for un-justified exposures to radiation and radioactive materials based on business economics.
Numerous national and international bodies provide recommendations on radiation protection, some of which have no regulatory authority, but their recommendations often serve as the basis for many of the regulations on radiation protection adopted by regulatory bodies. Federal and State agencies are tasked with passing laws and implementing regulations based on the recommendations of the advisory organizations, industry, and the public.
The following sections address the regulatory aspects of TENORM from a Federal, State and International level. There is a section on the major documents that are used as a basis for the proposed regulations, and a discussion of the current regulatory efforts.
The underlying philosophies of radiation protection and definition of dose have evolved over time:
Early protection philosophies were based on individual protection from acute doses (such as the tolerance dose), after nuclear weapons testing and civilian power reactors were built, protection philosophies were expanded to encompass chronic exposures to populations (collective dose) notably with respect to genetic doses. Finally, regulations addressing sources of radiation were promulgated to mitigate doses to receptors
(such as the NESHAPS). As these concepts expanded and more "stuff" came under control, it was put forth that some practices and small amounts/volumes of radioactivity or radiation could be excluded from regulation. Thus, the exemption and clearance issues came into being.
Exclusion
Exclusion covers activity sources not amenable to control, such as 40K in the human body, cosmic radiation, etc. It has been used interchangeably with exemption, but there are differences. Items or practices that are excluded from control never enter the regulatory arena, they are not examined and then determined to be exempted.
Exemption
Exemption had earlier been used to denote all radioactive material placed outside regulatory control because of the low risk they give rise to and because control would be a waste of resources. Later this term has been restricted to cover radioactive sources which never enter the regulatory regime, typically small sources such as tracers used in research, calibration tracers, and some consumer products containing small sources or low levels of activity per unit mass. Exemption can be carried out for entire practices or for sources within a practice. It is always linked to specific regulatory controls. The exemption may be from all of these controls or only some of them, and may have conditions attached.
Clearance
Clearance can be carried out for materials which, by their nature or location or both, have been subject to regulatory controls. In its most general form (unconditional clearance) it allows the unrestricted disposal, re-use or recycling of material, with no further control once the material leaves the originating facility or practice being regulated.
Practice
Any human activity that introduces additional sources of exposure or exposure pathways or extends exposure to additional people or modifies the network of exposure pathways from existing sources, so as to increase the exposure or the likelihood of exposure of people or the number of people exposed. Another definition is: a human activity that can increase the exposure of individuals to radiation from an artificial source, or from natural source where natural radionuclides are processed for their radioactive, fissile or fertile properties, except in the case of an emergency exposure.
The radiation protection principles for practices are:
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Justification: The overall effect of activities involving risks from radiological hazards should be to do more good than harm. "No practice involving exposures to radiation should be adopted unless it produces sufficient benefit to the exposed individuals or to society to offset the radiation detriment it causes."
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Optimization of protection: Radiological risks should be managed so that they are as low as can reasonably be achieved. "In relation to any particular source within a practice, the magnitude of individual doses, the number of people exposed, and the likelihood of incurring exposures where these are not certain to be received should be kept as low as reasonably achievable, economic and social factors being taken into account. The optimization should be constrained by restrictions on the doses to individuals (dose constraints), or the risks to individuals in the case of potential exposures (risk constraints), so as to limit the inequity likely to result from the inherent economic and social judgments."
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Limitation, or Protection of the individual: Measures to protect people from radiological risks should aim to limit the inequity that may arise from a conflict of interest between individuals and society as a whole. "The exposure of individuals resulting from the combination of all relevant practices should be subject to dose limits, or to some control of risk in the case of potential exposures. These are aimed at ensuring that no individual is exposed to radiation risks that re judged to be unacceptable from these practices in any normal circumstances. Not all sources are susceptible to control by action at the source and it is necessary to specify the sources to be included as relevant before selecting a dose limit."
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Intervention:
'Any activity that decreases overall exposure by removing existing sources, modifying pathways, or reducing the number of exposed individuals." It is also defined as "any action intended to reduce or avert exposure or the likelihood of exposure to sources which are not part of a controlled practice or which are out or control as a consequence of an accident."
The concept of intervention (distinct from other practices) is based on general principles of:
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Justification: The proposed intervention should do more good than harm, I.e., the reduction in detriment resulting from the reduction, in dose should be sufficient to justify the harm and costs, including social costs, of the intervention."
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Optimization: form, scale, and duration of the intervention should be optimized so that the net benefit of the reduction of dose, i.e., the benefit of the reduction in radiation detriment, less the detriment associated with the intervention, is maximized."
Individual limits: "Dose limits do not apply in the case of intervention."
Note: In the US, there are recommended worker dose limits for remediation or interventions.
The International Commission on Radiation Protection (ICRP) is an association of scientists from many countries, including the U.S. that develops recommendations on all aspects of radiation protection. It is an advisory organization with no regulatory authority, but its recommendations greatly influence the development of standards around the world. The primary document outlining the system of radiation protection being adopted world-wide is ICRP Publication 60
(ICRP 1990). This document outlines the system to regulation of sources as well as individuals. It is based on general principles with respect to practices: justification, optimization of protection, and limitation (individual dose limits). The concept of intervention (distinct from other practices) is based on general principles that: the intervention should do more good than harm; and the form, scale, and duration of the intervention should be optimized. For the public, an annual limit on effective dose of 1 mSv (100 mrem), with a subsidiary limit in some years, provided the average over five years does not exceed 5 mSv (500 mrem). It also recommends treatment of potential exposures, e.g., practices which may lead to interventions.
ICRP 65 addresses indoor radon, both for the public and in occupational settings, and gives recommendations for practices and interventions (ICRP 1994). Buckley, et.al., (Buckley 1997) identifies provisions ICRP 60 has that are of particular relevance to current initiatives in the U.S. and for the EU countries:
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The drawing of clear distinction between the twin concepts of "practices" and "interventions";
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The more explicit treatment of intervention, and the development of the intervention principles;
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Introduction of lower dose limits, coupled with a five year dose limitation period for the adult worker limit;
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Concept of dose constraints as an elaboration of the principle of optimization; and
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The need to bring natural radiation into the system in situations where there is a basis for exercising control.
The International Atomic Energy Agency (IAEA) published standards based on the recommendations of the ICRP and other organizations. The Euratom treaty of 1957 prescribes that uniform basic safety standards (BSS) shall be prescribed. The first Directive was issued in 1959, and was revised over the years. The current revision to the Basic Safety Series was issued as Principles for Exemption of Radiation Sources and Practices from Radiological Control, Safety Series 89 (IAEA 1988). A draft revision, International basic safety standards for protection against ionising radiation and the safety of radiation sources was published in 1994. It introduces the distinction between practices and intervention and the concepts of dose constraint and potential exposure.
There are two basic criteria that can determine whether or not a practice can be a candidate for exemption from the BSS:
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Individual risks must be sufficiently low as not to warrant regulatory concern; and
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Radiation protection, including the cost of regulatory control, must be optimized.
The guide states that an individual effective dose of 10 - 100 µSv (1 to 10 mrem) per year would result in insignificant risks. Based on the possibility of multiple exposure from several exempted practices, the guidance recommends an annual de minimis dose of 10 µSv (1 mrem). The proposed HPS/ANSI 13.12 recommendations have some similarities to the Safety Series 89 limits. The EC issued a similar council directive in 1996. Current revisions to the EC BSS were due by May 2000. Additional BSS documents have been published that give measurable quantities to the dose limits in Safety Series 89 (IAEA 1992).
The Draft Euratom Basic Ssafety Standards Directive,Version 24 February, 2010 affect TENORM in the EU.
The draft is not complete; not all limits and values have been set. Many carry forward from the 1996 draft discussed below.
Supporting guidance will be developed based on the latest BSS. It is up to the individual Countries to adopt the standards into their statutes and regulations.
"The subject matter and general purpose of this Directive is the health protection of the public, patients and workers against the dangers of ionising radiation; this Directive also applies to the protection of the environment as a pathway from environmental sources to the exposure of man, complemented where appropriate with specific consideration of the exposure of biota in the environment as a whole; in addition to the general purpose of health
and environmental protection this Directive also aims at ensuring adequate control of the safety and security of sources and the provision of appropriate information in an emergency exposure situation." ... "It shall apply to any planned, existing or emergency exposure situation which involves a risk from exposure to ionising radiation which cannot be disregarded from the radiation protection point of view with regard to the health protection of workers, members of the public, or patients and other individuals subject to medical exposure or with regard to the protection of the environment.
This Directive shall apply to all planned exposure situations involving radiation sources,namely:
(a) the production, processing, handling, use, storage, holding, transport, shipment,
import to, and export from the Community and the disposal of radioactive material;
(b) the operation of electrical equipment emitting ionising radiation;
(c) exposure situations which involve the presence of natural radiation sources that lead
to a significant increase in the exposure of workers or members of the public, in
particular:
(i) the operation of aircraft and spacecraft
(ii) exposure to radon in workplaces
(iii) the activities in industries processing materials with naturally occurring radionuclides, or activities related to such processing,
(d) any other activity specified by the Member State.
4. This Directive applies to existing exposure situations other than those involving exposures excluded under Article 3; it applies in particular to the exposure of the public to indoor radon and to external exposure from building materials; cases of lasting exposure resulting from the after-effects of an emergency or a past activity shall be dealt with as an existing exposure situation.
The draft replaces the 1996 draft (Euratom 1996 ). The document is entitled "Council Directive 96/29Euratom (OJ L159 29th June 1996)" which are just called the "Basic Standards Directive". It is similar in many ways to the IAEA BSS. The EC BSS list of exemption values covers only practices (Menem 1998).
Note emphasis on building materials, indoor radon, and specific call out of NORM. This is not seen in US regulations.
List of industrial sectors involving naturally occurring radioactive material
When applying Article 50 the following list of industrial sectors involving naturally occurring
radioactive material, including relevant secondary processes, shall be taken into account:
- - Extraction of rare earths from monazite
- - Production of thorium compounds and manufacture of thoriumcontaining
products
- - Processing of niobium/tantalum ore
- - Oil and gas production
- - Geothermal energy production
- - TiO2 pigment production
- - Thermal phosphorus production
- - Zircon and zirconium industry
- - Production of phosphate fertilisers
- - Cement production, maintenance of clinker ovens
- - Coal-fired power plants, maintenance of boilers
- - Phosphoric acid production,
- - Primary iron production,
- - Tin/lead/copper smelting,
- - Ground water filtration facilities,
- - Mining of ores other than uranium ore.
Annex 14
Indicative list of types of building materials considered for control measures with regard to their emitted gamma radiation
1. Natural materials
- - Alum-shale
- - Building materials or additives from natural igneous origin, such as:
- - Granite,
- - Gneiss,
- - Porphyries,
- - Syenite,
- - Basalt,
- - Tuff,
- - Pozzolana,
- - Lava.
2. Materials incorporating residues from industries processing naturally occurring
radioactive material, such as:
- - Fly ash
- - Phosphogypsum
- - Phosphorus slag
- - Tin slag
- - Copper slag
- - Red mud (residue from Aluminium production)
- - Residues from steel production
The 1996 Directive:
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Distinguishes between "practices" of the nuclear industry, and "work activities" where radioactivity is incidental, but can lead to significant exposure of workers or the public.
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Recommends exposure limits and exemptions from various sources of radioactivity, including NORM,
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Authorizes specific practices without any regulatory controls,
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Endorses ALARA, including provisions for justification, optimization, and dose limitations for specific practices,
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Includes provisions for alternate criteria, through dose assessments, for demonstrating when a practice or exemption is at its optimum, but exceeds the basic criteria,
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The Directive provides the following exposure limits:
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Maximum annual dose limit of 1 mSv (100 mrem) to members of the public, with a provision for allowing higher doses in any single year, provided that the average over five consecutive years does not exceed 1 mSv per year.
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Specific practices may be exempted if the resulting annual dose is less than 10
uSv (1 mrem) and collective effective dose in any one year does not exceed 1 man-Sv (100 person rem).
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1 mSv (0.1 mrem/hr) at a distance of 0.1 meter from any material or items containing radioactive materials in excess of the above limits, provided that materials are contained in the form of a sealed source and that conditions for their disposals have been identified.
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The limit on effective dose for exposed workers shall be 100 mSv (10 Rem) in a consecutive five-year period, subject to a maximum effective dose of 50 mSv (5 rem) in any single year.
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Clearance levels for releasing materials and items with concentrations and total activity below specific levels include are presented in Table 5. Clearance limits are being developed for bulk, volumetric materials (soils, concrete) as well as surface limits.
Table 5. EC Clearance levels
| Radionuclide |
Quantity |
Concentration |
| 40K |
106 Bq (27 mCi) |
100 Bq/g (2.7 nCi/g) |
| 226Ra and progeny |
10,000 Bq (270 nCi) |
10 Bq/g (270 pCi/g) |
| 232Th (secular equilibrium) |
1,000 Bq (27 nCi) |
1 Bq/g (27 pCi/g) |
| 238U (secular equilibrium) |
1,000 Bq (27 nCi) |
1 Bq/g (27 pCi/g) |
There is concern about the clearance levels, and exemption levels among the EC members.
TITLE VII Significant Increase In Exposure Due To Natural Radiation Sources. This section addresses occupational exposure to NORM:
This section is the subject of much debate, and may be the basis for guidance or regulation in the US someday. This section is one of the reasons that the EU countries are slow to adopt the BSS.
Work Activities:
"… within which the presence of natural radiation sources leads to a significant increase in the exposure of workers or of members of the public which cannot be disregarded from the radiation protection point of view."
It requires each Member State shall ensure the identification…of work activities which may be of concern. These include, in particular:
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… thoron or radon daughters or gamma radiation or any other exposure in workplaces such as spas, caves, mines, underground workplaces and aboveground workplaces in identified areas;
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… involving operations with, and storage of, materials, not usually regarded as radioactive but which contain naturally occurring radionuclides, causing a significant increase in the exposure of workers and, where appropriate, members of the public;
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… which lead to the production of residues not usually regarded as radioactive but which contain naturally occurring radionuclides, causing a significant increase in the exposure of members of the public and, where appropriate, workers;
The sections addressing protection from exposure from terrestrial natural radiation sources and protection of air crews shall apply to the extent that the Member States have declared that exposure to natural radiation sources due to work activities identified in accordance with paragraph 2 [the first two bullets under "Work Activities]" of this Article needed attention and had to be subject to control.
Protection against exposure from terrestrial natural radiation sources:
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"…for each work activity declared by them to be of concern, the Member States shall require the setting-up of appropriate means for monitoring exposure and as necessary, the implementation of corrective measures to reduce exposure."
Protection of Air Crew:
Each Member State shall make arrangements for undertakings operating aircraft to take account of exposure to cosmic radiation of air crew who are liable to be subject to exposure to more than 1 mSv per year. The undertakings shall take appropriate measures, in particular:
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to assess the exposure of the crew concerned,
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to take into account the assessed exposure when organizing working schedules with a view to reducing the doses of highly exposed aircrew,
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to inform the workers concerned of the health risks their work involves,
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to apply Article 10 [constraints on exposure to pregnant women] to female air crew.
NOTE: Remember the discussion about bringing the receptor closer to the source!
Additional supporting documents:
Note: This section is taken from an article by Simmons 2000:
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Radiation Protection 95: Reference levels for work places processing materials with enhanced levels of naturally occurring radioactive materials (1995),
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Radiation Protection 107. Establishment of reference levels for regulatory control of workplaces where materials are processed which contain enhanced levels of naturally-occurring radionuclides (1999).
These documents outline the process to assist regulators in identifying industries of concern with NORM for worker protection. They are used to establish dose-based reference levels for regulatory control. Worker doses from a given work activity/NORM containing material combination and extrapolating to identify the activity concentration or NORM in material processed, and eventually establish the level of regulatory control for that industry.
It involves a tiered system of "control bands" each of which defines a level of stringency
intended to correspond to worker risk from exposure to workplace NORM. The bands are graded according to effective dose to workers under "normal" and "unlikely" exposures.
It supports the use of screening levels for NORM. Three materials screening levels, based on specific activity of the "most significant nuclide (or nuclide segment)" establish the boundaries between the control bands.
Table 6. Radiation Protection 95 Control Bands
| Control Band |
Level of Control |
|
Effective Dose |
| |
|
Normal |
Unlikely |
| 1 |
No regulations |
<1 mSv/y |
< 6 mSv/y |
| 2 |
Lower level regulation |
1 mSv/y
| 6 mSv/y
| |
| 3 |
Higher level regulation |
6 mSv/y
| 20 mSv/y < dose <50mSv/y |
|
| 4 |
Process not permitted
unless dose can be
reduced |
> 20 mSv/y |
> 50 mSv/y |
United Kingdom
The U.K. regulations are codified in the Radioactive Substances Act of 1993 (UK 1993) and the Ionizing Radiation Regulations of 1999 (UK 1999). The main issues in Great Britain hampering adoption of the English version of the BSS have been over exemption for watches, and more importantly, clearance levels. The proposed clearance levels in GB are considerably more restrictive for most radionuclides than those of the EU. The concept of clearance does not appear explicitly in current UK legislation or regulatory guidance and there are no UK clearance levels which are described as such. There are, however, levels in current UK legislation which could be used for unconditional clearance of large volumes of material (DETR 2000).
Radioactive Substances Act of 1993
The following is excerpted from (DETR 1999):
Levels of man-made radionuclides:
The Radioactive Substances (Substances of Low Activity) Exemption Order (SoLA EO), made under the Radioactive Substances Act, gives general exemption from registration and authorisation for materials containing low levels of radioactivity. The 0.4 Bq/g concentration level in the SoLA EO is, in effect, an unconditional clearance level for solid materials. It applies to all man-made radionuclides, regardless of their radioactive half-life and their relative radiotoxicity.
Levels of naturally-occurring radionuclides in the uranium and thorium series:
Schedule 1 of the Radioactive Substances Act 1993 sets out concentrations of radioisotopes of uranium, thorium, radium, actinium, protactinium, polonium and lead in solid materials below which these materials are, for the purposes of the Act, not considered to be radioactive. The Schedule 1 concentrations are… exemption levels but within the current UK legislative framework they could also be used as unconditional clearance levels. The … levels are in terms of total concentrations of the specified radioelements, including the natural background concentrations, because it is easier to apply exemption levels of naturally-occurring radionuclides which are expressed in this way. [See Appendix B for the tables]
It is not clear if the U.K. will change their regulations to be more consistent with the EU.
Ionizing Radiation Regulations of 1999
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Worker exposures greater than 1 mSv/y are "Significant",
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Scope of regulation includes NORM,
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Licensing (prior authorization) for practices involving exposure to ionizing radiation,
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Notification if work activities exceed 10Bq/g (270 pCi/g) Ra-226, 1 Bq/g (27 pCi/g) Th-232 and 1 Bq/g (27 pCig) U-238 (all in equilibrium).
Regulation of NORM in Canada falls to the Provinces and Territories. The Federal Provincial Territorial Radiation Protection Committee (FPTRPC) recognizes that the potential radiation hazards from NORM are the same as those from regulated sources, and believes that similar levels of protection should be applied to both regulated workers and those workers and public exposed to NORM. To that end, the FPTRPC, through the Canadian NORM Working Group produced the draft Canadian Guidelines for the Management of
NORM (FPTRPC 2000). The work is an extension of earlier work done by The Western Canadian Committee on NORM, published in 1995 as the Guidelines for the Handling of NORM in Western Canada. Guidelines are being developed to:
- Ensure adequate control of NORM encountered by affected industries,
- Harmonize standards
- Reduce jurisdictional gap or overlap.
The guidelines are based on ICRP recommendations and has a goal of ALARA. No distinction is made regarding the origin of the radiation, whether it is NORM in its natural state, or TENORM. A unique feature of the Canadian guidelines is the adoption of a NORM management program, based on classification of hazards. This results in a graded approach to worker protection.
The recommended radiation dose limits are defined in terms of incremental dose, which is the dose resulting from the work practice in question. Natural background and medical doses are excluded.
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Occupationally exposed workers are employees who are exposed to NORM sources of radiation through their regular duties. They are classified as NORM workers working in an occupational exposure environment, and their annual effective dose must not exceed 20 mSv (2 rem)
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Incidentally Exposed workers are other employees whose regular duties do not include exposure to NORM sources of radiation. They are considered as members of the public who work in an occupational exposure environment and, as such, the annual effective dose limit for these workers is 1 mSv (100 mrem).
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Dose constraint from a single source limited to 1/3 of the public dose limit of 0.3 mSv/y (30 mrem/y).
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Guide includes release limits that will not cause doses in excess of 0.3 mSv/y (30 mrem).
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The NORM investigation threshold of an incremental dose of 0.3 mSv/y (30 mrem) is proposed for where doses to workers or members of the public may possibly exceed this value; an assessment should be carried out.
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The NORM management threshold of an incremental dose of 0.3 mSv/y (30 mrem) to the public or workers is proposed.
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A Dose Management Threshold is an incremental dose of 1 mSv/y to a worker.
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The Radiation Protection Management Threshold is either assessed or measured incremental worker dose of 5 mSv/y (500 mrem/y).
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Standards for transportation of NORM, Derived working limits for NORM, and NORM material management are also proposed.
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Derived release limits for diffuse and discrete NORM sources are proposed. Excerpts from the tables can be found in Appendix B.
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