In view of the increasing use of radiation and radioisotopes for various beneficial applications, it was found necessary that the unnecessary exposures should be avoided and the necessary exposures should be minimized or optimized. The principle underlying the philosophy of radiation protection and safety is to ensure that there exists an appropriate standard of protection and safety for humans without unduly limiting benefits of applications of radiation and radioisotopes. Internationally agreeable protection standards, called Basic Safety Standards (BSS) were developed over the years by the IAEA. The standards place requirements on those persons authorized to conduct justified practices that cause radiation exposures in existing exposure situations. Requirements are also given to intervene in order to reduce exposures. The BSS also recommend procedures for ensuring the safety of radiation sources, for emergency preparedness and response for mitigating the consequences of accidents.
Some of the unjustified practices are: addition of radioactive materials to food, beverages or cosmetics; use of radioactive materials in toys and jewelry, and certain medical exposures like mass screening of population groups.
The objective of the BSS is to prevent the occurrences of short-term effects of high doses of radiation and to restrict the likelihood of occurrence of long-term stochastic effects. Implementations of these standards are the responsibility of national regulatory body. It is the responsibility of the government to establish national regulatory infrastructure to regulate these activities and to provide adequate resources required for the effective implementation of the regulatory requirements. The regulatory Authority is empowered through legislation to enforce the legislation and carryout the regulatory activities at the national level.
Exclusion
Radiation exposures whose magnitude and likelihood essentially un-amenable to control are excluded from regulatory control. Examples are exposures from K-40 radioisotope present in the body, cosmic radiation at the surface of the earth, and low concentrations of natural radionuclides in materials.
Exemption
Exemption is used to avoid unnecessary regulation of practices involving inherently safe sources, with trivial radiological consequences.
The retail sale of smoke detectors containing small amount of radioactive material can be dealt with exemption criteria. The BSS provide the exemption levels for different radionuclides in terms of activity concentration, total activity or dose rate on sources, which may be exempted without further analysis or other considerations.
Clearance
Clearance refers to sources and materials which have been within a regulatory system, but which have been treated or have reached a condition such that regulatory controls can be lifted. The criteria for clearance are essentially same as for exemption. Typical IAEA suggested clearance levels for Cs-137 for unconditional releases, for recycling in steel, for landfill disposal and for incineration are: 0.1 Bq/g, 0.5 Bq/g, 1 Bq/g and 3 Bq/g respectively.
Safety in transport of radioactive materials
Transport of radioactive materials is strictly controlled by the regulatory body to ensure safe transport, and response in case of any unusual incidents involving the source during the transport. Appropriate controls on quantity, radiation dose, packaging, labeling, etc are necessary to transport the sources through different modes like air, road, rail, etc. For details, see the reference book, Radiological Protection and Safety – A Practitioner’s Guide (2019), with relevant references.
Type of regulatory controls
The type of regulatory controls depends on the level of risk or complexity associated with the practices.
Notification
Notification is applied to the lowest order of risk or complexity. A legal person, through a document notifies the possession of a source or the intention to carry out a practice. The notification may be the only requirement if the regulatory authority is convinced that the normal exposures are expected to be very small and the likelihood and magnitude of potential exposure are negligible. However, the notification is not adequate for practices such as uncontrolled radioactive waste disposals. Notification provides important information necessary for regulatory decisions, such as the data about distribution, volume, pattern of use and disposal.
Registration
Registration is a relatively simple and efficient authorization mechanism. The registration applicant provides information such as:
- Clear identification of the source, associate facilities and equipments to be utilized in the practice,
- The location of use,
- Identification of the individual responsible for source safety and
- Acceptance of all applicable operating, maintenance and disposal requirements for the specified source.
Based on the generic safety assessment of the design, equipment, operating procedures, maintenance, training requirements, etc safety requirements are established and the application for registration may be approved.
Licensing
Licensing is required for all complex operations such as nuclear fuel cycle operations, medical applications and industrial radiography. The application for licensing should contain detailed information related to the source, radiation protection and the source safety provisions, an assessment of the nature, magnitude and likelihood of the exposures attributed to the source. The application is evaluated for compliance with respect to the applicable requirements and regulations. The license is issued to use the sources for the specific purpose within the boundary conditions and other stipulations given in the license, for a specified period of time.
The legal person bears the primary responsibility for ensuring compliance of the requirements for the protection and safety of the sources for which the person is authorized. The authorization procedures may be different in different countries depending upon the nature of the source, operations and the availability of the regulatory infrastructures.
In India, a very well-developed regulatory infrastructure exists to regulate all the activities involving radiation and radioisotopes, including all the nuclear fuel cycle operations. Atomic Energy Act of 1962 was formulated, which enabled framing of several rules related to radiation safety of the facilities in the country handling radioactive materials and radiation generating equipments. These are listed below:
- Radiation Protection Rules, 1971, 2005
- Industrial Radiography procedures, 1980
- Atomic Energy (Factories) Rules, 1988, 2005
- Atomic Energy (working of mines, minerals & handling of prescribed substances) Rules, 1984
- Environment (Protection) Act, 1986
- Environment (protection) Rules, 1987
- Safe Disposal of Radioactive Waste Rules, 1987
- Control of Irradiation of Food Rules, 1990
The Government of India constituted the Atomic Energy Regulatory Board (AERB) in 1983 with a mandate to carryout regulatory and safety functions under the Atomic Energy Act, 1962. The AERB issues standards, several codes and guides on various topics related with the application of radiation and radioisotopes. The regulatory body is located at the Niyamak Bhavan, Anushaktinagar, Mumbai–400094, India. Any person intending to handle radioactive source should apply to AERB for authorization. The mission of the AERB is to ensure the use of ionising radiation and nuclear energy in India does not cause undue risk to the health of people and the environment.