Radiation that needs caution

In recent times, India has been witnessing an exponential increase in the use of radiation and radioactive sources in medical, industrial and research applications, accruing huge societal benefits to the country.

The sources used are of various radionuclides in different physical and chemical forms, with their strengths of radioactivity varying from few hundreds of becquerel (one becquerel corresponds to one disintegration or nuclear transformation per second) to billions of becquerel. These sources are handled in a variety of environments — from research laboratories, universities to industries and hospitals. But has anyone wondered about the safety of such usages? Clearly, the regulation of the risk from such practices poses a great challenge.

Yes, the benefits of radiation are countless. For instance, nuclear medicine uses radiation to provide diagnostic information about the functioning of a person’s specific organs or how to treat them. Diagnostic procedures using radioisotopes are now routinely done.

A gamma camera captures the image from the points from which radiation is emitted. This image is then processed and presented by a computer to the physician for indications of any abnormal conditions. Different isotopes are used for targeting different organs. For example, Tc-99m is the most commonly used radioisotope in nuclear medicine for imaging and functional studies of the brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood and tumours.

A more recent development in nuclear medicine is the Positron Emission Tomography (PET), whose important clinical role is in oncology, with fluorine-18 as the tracer. It is proven to be the most accurate non-invasive method of detecting and evaluating most cancers. 

When it comes to commercial usages, the applications of radioisotopes in industry are numerous. Nucleonic measurement and control devices, popularly known as nucleonic gauges, are used in several industries for the measurement and control of process parameters such as thickness, density, level and composition. Many types of thickness gauges make use of the attenuation property of gamma rays passing through a material, which is used in common industrial applications, such as testing the quality of metals and composites in manufacturing industry, gauging the density of road surfaces, measuring the storage levels in material containers like coal bins etc. 

The need to regulate

In such conditions, it is important to have in place a regulatory system to keep track of all the radiation sources in the public domain. The basic nuclear legislation in India is the Atomic Energy Act, 1962, which requires the central government to issue rules relating to safety of workers, public and the environment, in the context of work with ionising radiations and that a competent authority be appointed for the enforcement of the rules.

Atomic Energy (Radiation Protection) Rules, 2004, issued under the Act stipulate the licensing requirements for handling radioactive materials and operating radiation installations. The Atomic Energy Regulatory Board (AERB) in Mumbai is the competent authority for the enforcement of the rules. 

Regulatory control over the radiation sources is exercised in three stages: in the pre-licensing stage, it is ensured that the installation, equipment and sources are designed and made as per AERB approved standards, to meet the safety and security requirements. The applicant should have well drawn out operating procedures, adequately trained manpower, appropriate radiological protection programme and emergency response plans. During the operational stage, all licensees are required to send periodic safety status reports.

Systems in place

Regular and surprise inspections are carried out by AERB inspectors to ensure that the operations are conducted in compliance with the licensing conditions. Finally, in the decommissioning stage upon completion of the useful life of the facility or the source, the licensee returns the source to the original supplier or to an authorised agency.

Disused sources not properly disposed off can find their way to the public domain through scrap dealers. This is exactly what happened in the case of Mayapuri incident in April 2010, in which one scrap dealer lost his life after receiving high doses, due to the negligence of the Delhi University in disposing off the radioactive source.

AERB has constituted an apex committee called Safety Review Committee for Applications of Radiations (SARCAR) for making recommendations on applications seeking regulatory approvals. SARCAR recommends granting design or type approval of radiation sources, radiation devices, transport packages, consumer products, radiation equipment and facilities, based on safety review and assessment of applications. It also advises AERB on education and training programmes related to radiation safety. 

The Department of Atomic Energy (DAE) of the Government of India has also put in place a Crisis Management Group (CMG) to co-ordinate between various state and central agencies to facilitate a well-structured and effective response to radiological emergencies in the public domain. Public functionaries like custom officials, police and fire brigade personnel are also being trained in handling such emergencies as first responders.

While a central Emergency Control Room (ECR) has been established in Mumbai, there are several Emergency Response Laboratories (ERL) operating in different regions of the country, so that the response functions can be initiated within hours of the incident being reported.

Recently, AERB has launched a programme of e-Licensing of Radiation Applications (e-LORA), a web-based integrated licensing and tracking system for regulating all types of radiation facilities in the country. Now, the stakeholders across the country have easy access to AERB through the internet. This system allows the applicant to submit his application along with the required details, track the status of his application and obtain the approval document.

The system also enhances the efficiency and transparency of the regulatory process and has also resulted in achieving paperless licensing process. It enables AERB to track the radioactive source from the cradle to the grave, thereby ensuring the safety and security of the source. More than 9,000 institutes are operational in eLORA now and it has a database of more than 10,000 radiation professionals and 24,000 radiation workers.

(The author is chairman, SARCAR, AERB)