Controlling and Managing Radioactive Sources

Abstract

This chapter discusses the dangers of uncontrolled or orphaned radioactive sources. From the Indian perspective, N. Ramamoorthy provides an overview of the importance of legitimate industrial and medical uses of radioactive materials. He argues that such applications preclude a one-size-fits-all approach to security. To mitigate the problem, Ramamoorthy argues for the use of non-radiological alternatives where possible, and for better accountability and proliferation-proof designs where there is no alternative. U.S. authors Christopher Boyd and Anne Wiley explain that radiological sources can provide material for dirty bombs, and are often located in areas with relatively lax security environments. To address this problem, the authors argue for regulatory flexibility and, where possible, for risk elimination rather than risk mitigation.

6.1 An Indian Perspective

This article is based on the career experience of the author as the Head of the radioisotope and radiation technology programme concurrently at both BARC (as Associate Director) and BRIT (as Chief Executive), India during August 2000–September 2003, and subsequently at the IAEA (as Director of NAPC) during October 2003–March 2011, as well as his current role as the Chairman of the Apex Advisory Committee called SARCAR (Safety Review Committee for Applications of Radiation) of AERB, India, from June 2016 onwards. All the views expressed in the article are personal, professional ones of the author and not necessarily those of the organisations shown above as author’s past and current affiliation.

• N. Ramamoorthy 

This chapter deals with the Indian policy, practices, and experiences in managing and controlling radioactive sources. The second section details the processes in place to control and secure radioactive sources in major areas of their applications. The section also examines the human element and legacy issues and related incidents and lessons. The third section outlines the production of RI-based sources and operation of radiation technology facilities and services. The fourth section looks at the IAEA support and contributions with regard to safety and security of radioactive sources. The fifth section looks at the interface between safety and security of these sources while the sixth section suggests measures to strengthen the control of the use of radioactive sources and ways to foster alternative technologies. The final section looks at the continuing challenges and the way forward with a few recommendations.

6.1.1 Introduction

The field of ionising radiation, in terms of technologies and their multiple applications, has continuously evolved over time and is well-recognised worldwide for delivering numerous societal benefits. In particular, the benefits accruing to industries and healthcare are invaluable. As a result, radiation technology and its utilisation are now spread across the world, including in developing countries and in small and large nations. The IAEA, as the global forum for all matters nuclear, has an extremely important role in supporting the interested Member States (MS) in the adoption of radiation technologies, capacity building, and fostering safety and security in all practices involving the use of ionising radiation, along with appropriate regulations. The IAEA’s Ministerial Conference on “Nuclear Science and Technology: Addressing Current and Emerging Development Challenges” held in November 2018, was a large event, with over 160 Member States of IAEA, 54 Ministers, and about 1100 national delegates in attendance. The Ministerial Declaration succinctly portrays the status and trends in the field.¹ Among the various practices in vogue, the use of high-intensity, high-risk radioactive sources—made of radioisotopes (RI) such as ⁶⁰Co, ¹³⁷Cs, among others—has been attracting increasing global attention for the past 20 years—especially after the 9/11 terrorist attack in USA in 2001. Consequently, several national leaders have repeatedly called for strengthened nuclear security measures and cooperation, most notably in the Nuclear Security Summit biennial events held from 2010 to 2016. The appeal includes efforts concerning high-intensity radioactive sources cited above. It is against this backdrop that the current article on “Controlling and managing radioactive sources” is presented describing the status of the field, the Indian experience, and the global scenario based on IAEA documents and events, as well as the challenges to be addressed and certain options and recommendations for the path forward.

There has been consistent interest in exploring and deploying the beneficial uses of radioactive materials. The use was initially confined to natural sources and has subsequently been based on the vast range of radioisotopes (RI), which could be produced in nuclear reactors and charged-particle accelerators. The ensuing applications based on ionising radiation are well established in industry, healthcare, food and agriculture and research (Ramamoorthy WNU 2019; Gopinath and Ramamoorthy 2020). They are not only harnessed by industrialised countries, but in almost all parts of the world, be it small or large nations, developing countries or low- and middle-income countries (LMICs).

The source of radiation in most of these cases has been radioisotopes (Table 6.1), e.g., ⁶⁰Co, ¹³⁷Cs, ¹⁹²Ir, coming under the class of radioactive (sealed) sources. The production of the RI-based sources and equipment containing RI has been confined to a limited number of countries at national centres and in private industry. Their deployment, however, has been very extensive, across the world and to a large extent in the public domain at hospitals, industrial sites, academic centres, and research labs. For example, RI-based sources of ¹⁹²Ir and ⁶⁰Co (high-intensity, sealed sources, and devices) are used for industrial applications such as radiography cameras and gamma radiation processing plants as well as for healthcare applications like radiotherapy for cancer patients (Ramamoorthy 2019, 1–12). Thus, movements of RI-containing packages/cargo are routine exercises throughout the year, with some being more frequent than others based on the half-life of RI involved and the need for source replacement or replenishment.

Table 6.1 Major types of RI source-based equipment and volume of use

In order to leverage alternative sources of radiation in certain types of applications, such as those requiring very high or very low dose rates, electron accelerators and X-ray systems have been developed. Many such systems are in regular use apart from the use of RI-based sources (Chmielewski and Haji-Saeid 2019, 37–44, Fidarova and Erbas 2019, 63–70). This has generally remained confined to the more industrialised nations.

The safety and security of radioactive sources has been a subject of high importance to stakeholders and national authorities (IAEA 2004, 1–16; Ranajit Kumar 2013; Upreti 2013, 146–149). The 9/11 events in the USA became a wake-up call to all countries. It forced the world to identify and analyse vulnerable areas, potential threats, and any possible risk to society. The widespread use of high-intensity radioactive sources has been naturally recognised as a crucial area of risk in this context. The large programme involving the use of RI sources has to ensure the availability of their benefits to society while protecting them from terrorists and criminals, who could use them to endanger public life, property, and the environment.² In this context, this chapter tries to capture the various facets of applications and vulnerabilities, the importance of addressing the security of radioactive materials, effectively controlling and managing the use of RI sources, and measures for possible paths forward. This manuscript was prepared prior to the launch of U.S. National Academy publication on Radioactive Sources (NAS 2021), an important reference on this subject (see Sect. 7.1).

6.1.2 Control and Security of Radioactive Sources in Major Areas of Their Applications

Three unique features of radioisotopes make them extremely valuable, predominantly for industry and healthcare (Gopinath and Ramamoorthy 2020). The first, popularly referred to as radiotracer principle, is based on open-source RI samples, mostly in liquid or solid form, and of low to medium level of radioactivity. These may not come under the high-risk category, unlike the other two areas where high-risk RI sources are commonplace (the categorisation of RI sources is covered later in this chapter). RI can use tracers to follow the movement of materials of interest with respect to time and space in both living and non-living systems, using the very high sensitivity for detection of RI radiation. This makes them one of the most powerful probes for non-invasive examination, often including imaging, in medicine, industrial processes and systems, civil structural integrity, biology, agriculture, drug development research, etc. Transmission and attenuation of radiation while penetrating through matter will reveal the inner details of the interposed objects depending upon their density, mass, atomic number, etc. This is the basic principle of all radiography procedures, whether it is in a medical or industrial area, or of civil construction and structures. Nucleonic gauges used in industries also fall in this category. The ability to deposit radiation energy (low-dose to high-dose) at the desired location inside exposed matter helps to bring about physical, chemical, and biological changes of the materials exposed to radiation. This enables applications ranging from cancer treatment to sterilisation of medical products, to disinfestation or hygienisation of food products, to manufacturing advanced materials (polymers, composites, cable insulation, etc.), to mitigation of certain pollutants.

A few specific areas of large-scale deployment of RI sources are discussed in the following sub-sections, keeping in mind practice-specific vulnerabilities.

6.1.2.1 Industrial Gamma Radiography (IR) Sources and Practices

The RI sealed sources of high-intensity ¹⁹²Ir 740 - 3700 GBq (20–100 Ci) and ⁶⁰Co up to about 11 TBq (300 Ci) are used in gamma radiography exposure devices, popularly known as radiography cameras. Industrial radiography (IR), as a key element of non-destructive testing/examination (NDT/NDE), is a vital feature of regular operations in several industries such as aviation, steel, oil and gas, and chemical large civil constructions such as bridges, dams, and many cases of establishing infrastructure (Venkatraman and Menaka 2020, 106–130). By the very nature of IR’s utility, the procedures are often carried out in open areas. Furthermore, devices with radioactive sources must repeatedly be transported from one site to another, often at very short notice. There is also stiff competition amongst IR service providers to secure orders, make maximum utility of each source/device, and perform radiography and deliver results as and when demanded by the contract-awarding party (CAP).

Advanced RF-based tracking of sources and devices, which has recently emerged in the IR sector, is an important step towards ensuring additional control over them (IAEA CN269 December 2018). The application of sealed-source techniques for trouble-shooting industrial processes and systems, such as gamma-column scanning in petrochemical plants and refineries, is popular in many countries including India (Jung 2019, 52–59; Pant 2020, 210–249). The source strength in some of these cases can be high (tens of GBq, a few Ci ⁶⁰Co), coming under Cat. 2 and can warrant measures similar to those applicable for IR devices/sources.

Another challenge is retaining qualified manpower. Well-qualified operators tend to move to greener pastures for better wages and benefits. This increases the challenge of ensuring operational safety as well as security of sources.

The number of RI sources and devices globally in use runs into tens of thousands, with over 2000 in India alone (Table 6.1). This creates a serious danger of theft and sabotage, though the source strength involved in IR devices is much lower than in the case of gamma radiation plants (PBq level, 0.1–5 MCi) and tele-cobalt units (tens of TBq, 10–12 kCi) (Ramamoorthy, IAEA conf 2018; Ramamoorthy, IAEA conf 2019). The latter two have a much higher degree of physical protection measures in place, being located within a specific campus, apart from other inherent system strengths.

6.1.2.2 Irradiator Plants (Gamma Radiation Plants)

There are over 250 gamma radiation plants in the world (www.iiaglobal.com; iiA brochure 2020; iiA white paper 2020; IAEA Directory 2004) and the number in India is over 20. The total installed strength of ⁶⁰Co in radiation plants in the world is about 500 MCi, while the actual physical loading can conservatively be taken as 40% at any given time. In India, there are over 20 gamma radiation-based processing units (20–110 PBq level, 0.5–3 MCi capacity) set up and operating in the private sector, in most cases handling both food and medical products. Another seven are under construction.³

Most of the gamma radiation processing plants are operated with quality-standard certifications issued by an accredited entity. These certifications attest to the plants’ compliance with well-established SOPs. They also indicate that the facilities have met source-security-related requirements against both theft and sabotage.

Despite these precautions, threats from malicious actors cannot be ruled out. Materials may be vulnerable to theft or tampering during transport. Such tampering could include the introduction of explosives into the shipment, resulting in damage to facilities. Because plant design and operation involves heavy shielding, any damage is likely to be contained. Nonetheless, malicious actors can cause damage.

Gamma radiation plants must undertake periodic source replenishment operations. For this purpose, large, heavy casks containing fresh-source pencils of high intensity are transported to and then handled within the premises. Spent sources may also be loaded into the same container and returned to the vendor, with adequate attention given to the security and safety of sources during transport (Nandakumar 2013, 131–134). Most of these operations with source pencils take place in the shielding water pool housing the source racks and are handled by experienced, qualified, and certified staff. Also, professional support is available from the vendor providing the sources, the personnel that provide regulatory oversight, and the radiation protection officers.

Though information on replenishment operations is not public, it could leak to malicious actors. They can target such operations, particularly through commando-type attacks, which can damage a facility and frighten the public. Sensitive information must therefore be shared between stakeholders, the operator-licensee and their staff, the vendor, and the regulator on a strictly “need-to-know” basis.

6.1.2.3 Radiotherapy: RI Sources and Systems for Cancer Care

In the area of healthcare applications, radiotherapy facility housing ⁶⁰Co sources and brachytherapy sources, mostly ¹⁹²Ir and also ⁶⁰Co, is commonplace in medical centres or hospitals for treatment of cancer patients (Table 6.1) (Fidarova and Erbas 2019, 61–70). Blood irradiator units containing ¹³⁷CsCl (74–111 TBq, 2–3 kCi) or ⁶⁰Co (30–37 TBq, 0.8–1 kCi) are deployed in many hospitals and blood banks (Table 6.1) for low-dose radiation (25–35 Gy) inactivation of T-lymphocytes in blood samples meant for transfusion to immuno-compromised patients. Almost all of these facilities are located in specific campuses, where physical protection, access control, and personnel reliability assessment are operative, reducing the scope for theft and sabotage of sources and equipment.

There has been greater concern over ¹³⁷CsCl source among national authorities and academic experts. This is due to its dispersible nature, and the 30-year half-life and 0.66 MeV gamma emission of ¹³⁷Cs. This creates the potential for heavy, large-scale contamination in the event of sabotage to systems containing ¹³⁷CsCl source.

Also, medical centers and hospitals, containing large numbers of people and lacking robust security, are attractive targets for malicious actors. Miscreants can potentially make a large impact and intimidate the public by attacking these types of sites. However, the design features of tele-cobalt units and BI units in these facilities include heavy shielding cum storage casks, which may withstand the impact of explosions triggered by attackers.

6.1.2.4 Other Areas of RI Source Applications

Laboratory Research Irradiators, called gamma chambers or gamma cells (GC), contain ⁶⁰Co source and have an irradiation chamber volume of a few litres’ capacity. They have played a central role in supporting radiation research studies focusing on food preservation, phytosanitary support for trade or shelf-life extension, polymer and composite development, treating seeds for preparing crop mutants, and sterilisation of male insects. In the past, such units housing ¹³⁷CsCl sources were also in use. In India, BRIT/DAE has since the 1990s developed and supplied gamma chambers to facilitate and catalyse radiation science R&D and allied applications. Low-dose rate gamma chamber units of ⁶⁰Co have also been supplied and used.

The utilisation of most of these units is in R&D and academic centres. Thus, access to these types of units is more easily controlled. Research interests may change with time, however, and scientists may move to different locations. The possibility of radiation equipment like gamma cells being abandoned therefore cannot be ruled out, notwithstanding the regulations that should preclude this. The Mayapuri incident in India, involving abandonment of an old GC unit belonging to Delhi University, illustrates this danger, as well as the challenges that authorities face in tackling such situations and striving for mitigation measures (Kumar et al. 2015, 517–528; IAEA 2015).

6.1.2.5 Human Element/Factor-Related Aspects

The human element—in particular the problem of human reliability—is an essential aspect of the safety and security-related efforts discussed above (Ramamoorthy, NIAS 2021; Ramamoorthy 2022). Insider threats can result in theft or sabotage of radioactive sources. A number of measures can address such insider threats and related risks. A human reliability assessment programme, consistent with the potential risk level due to the nature of RI sources, equipment, and plant, needs to be adopted by the employers and licensees acquiring Cat.1 and 2 sources. This may include formal vetting procedures for staff induction, training, periodic reviews, medical examination including psychometric tests, counselling, and mentoring of key staff. Further, crucial high-risk operations, such as ⁶⁰Co source loading or replenishment in irradiator plants, should be undertaken only after additional checks have been conducted on the team undertaking such operations. In addition, sensitive information related to high-risk sources regarding operations, storage, access control, and transport should be shared on a strictly “need-to-know” basis. Instituting appropriate protective measures towards ensuring information security is imperative to the management of radioactive sources.

6.1.2.6 ‘Legacy Source’-Related Events and Lessons

The regulatory systems of many countries have evolved and matured over time, but in light of the rather long half-life of many RI, e.g., 30 years for ¹³⁷Cs (in gamma cells), 432 years of ²⁴¹Am (in neutron source), as well as RI-based nucleonic gauges received with industrial machinery, legacy sources and equipment are present in many countries. While still in the early stages, a few applications involving radiation—mostly in medical and academic centres—have been established, preceding the formal regulatory system coming into vogue. The regulatory authority, or its delegated entity, has strived to map the legacy sources and equipment and to minimise the possibility of unregistered RI sources. However, this has not been an easy task. Incidents involving orphan and legacy sources have taken place.

Efforts to create a foolproof inventory of all high-risk (Cat. 1 and Cat. 2) RI sources assume great importance in this context. A comprehensive inventory scheme is essential for proper control and management of RI sources. Any sudden occurrence involving a newly recognised orphan source challenges the validity of the RI source inventory claims.

Cooperation and mutual support among all stakeholders will be crucial to efforts to track and inventory radiological materials, especially in regions experiencing instability due to conflict or the dissolution of states. The 2001 radiological accident involving orphaned sources in Lia, Georgia, is a case in point. In particular, help is needed to better control, track, and inventory unaccounted sources in conflict-ridden countries or regions; for example, the 2001 Georgia case (IAEA 2014) and the Mayapuri incident mentioned in the preceding sub-section. The technological tools adopted and experience gained in managing events like the one in Georgia have become useful additions to emergency preparedness in affected countries and around the world (IAEA 2014, 2015).

6.1.3 Production of RI-Based Sources and Operation of Radiation Technology Facilities/Services—Indian Experiences with Control of Sources

In India, Cobalt-60 is produced in large quantities (over 75 PBq level (2+ MCi) per annum) using some of the PHWR-type NPPs of NPCIL. Cobalt adjuster rods are used in place of the conventional SS adjuster rods enabling ⁶⁰Co production during NPP operation for power generation. A BRIT/DAE recovery cum processing facility, called RAPPCOF, is located in Rawatbhata. DAE/BRIT is one of the very few entities in the world that has large-scale ⁶⁰Co production and supply capacity as well as associated technology capabilities (www.britatom.gov.in).

BRIT/DAE has also established indigenously designed and constructed irradiator plants,⁴ leveraging its very early entry (1974) into gamma radiation processing.⁵ As cited in Sect. 3.2, there are over 20 gamma radiation-based processing units set up with DAE-provided technology and operating in the private sector, in most cases handling both food and medical products. BRIT/DAE expects to make available lifetime supplies of ⁶⁰Co indigenous sources for all these plants.

Bhabha Atomic Research Centre and BRIT have unique access to certain fission-product RI, which can be recovered only from the reprocessing stream of back-end fuel cycle operations. Exploratory efforts have delivered Cesium-137 (¹³⁷Cs) in vitrified form as a sealed source, for use in place of ⁶⁰Co in radiation equipment such as blood irradiators and low-dose laboratory research irradiators. BARC-developed vitrified ¹³⁷Cs source containing BI units also has been developed in the past few years (Patil et al. 2015, 55–63). The use of ¹³⁷Cs (30 y) obviates the need for source replenishment, which is required in the case of ⁶⁰Co-based BI units. Development of vitrified ¹³⁷Cs source provides technology superiority to ¹³⁷CsCl, which is vulnerable to sabotage due to its high solubility and dispersibility. It is, however, unlikely that such vitrified ¹³⁷Cs sources can find use in other applications such as radiation processing plants. This is due to the relatively larger dimensions of vitrified ¹³⁷Cs source pencils, lower penetration of 0.662 MeV gamma radiation (cf. 1.17 and 1.33 MeV of ⁶⁰Co), low density of radioactivity content, and likely non-homogeneity of radioactivity in the source matrix. In other words, the use of vitrified ¹³⁷Cs source will remain confined to low-dose-rate applications.

India’s national regulatory authority, the Atomic Energy Regulatory Board (AERB), has instituted a number of steps toward enforcing regulatory oversight functions related to radiation facilities and their applications, in line with experience gained over time and stakeholder feedback. The web-based e-LORA (e-Licensing of Radiation Applications) system has helped to enable registration, intimations, applications, approvals, accountability, and tracking.⁶ An annual interactive event, the National Conference of Regulatory Interface (NCRI) is another process to encourage frank feedback, disseminate lessons and experience gained, and suggest possible strengthening measures to consider. This has helped to inculcate a safety and security culture among stakeholders using RI sources, contract-awarding parties, and higher management teams in institutions where the radiation equipment may be a small part of a department or laboratory.

The expertise and infrastructure required for nuclear and radiological emergency preparedness and response (EPR), built up by DAE over time (Pradeepkumar 2013, 138–145; Murali 2020, 1–5), enables mandated authorities to manage any exigencies involving radioactive sources (especially Cat. 1 and 2 type). A Crisis Management Group (CMG; https://dae.gov.in/writereaddata/CMG_contact.pdf), comprising high-level professionals and senior management and with linkage to government officials of the region, is also in place at the DAE headquarters in Mumbai. There are 25 Emergency Response Centres (ERC), set up in different parts of the country, well equipped to support field operations. The various units of DAE spread across the country can further augment the resources of ERCs to support EPR-related activities as required.

Training events and exercises, involving personnel beyond the nuclear/radiological domain, are carried out regularly. The Global Centre for Nuclear Energy Partnership⁷ (GCNEP), located at Bahadurgarh, near New Delhi, has been functioning for over a decade and runs several training events both on and off campus. GCNEP schools dealing with Nuclear Security Studies and Radiological Safety Studies support the management and control of radioactive sources and offer necessary training and familiarisation to the various stakeholders. GCNEP is also helping to build expertise in nuclear forensics for managing EPR situations (Murali et al. 2014, 178–189).

Radioactive sources from old or abandoned academic, medical, or industrial equipment have in some cases required extensive DAE support for safe disposal or suitable storage. With the concurrence of the Government of India, the experts in units like BRIT and BARC have undertaken to provide it. Such cases needing national-level support for managing the end-of-life-time RI sources or equipment are common in other countries too.

Entities handling large-scale scrap metal waste, including from foreign sources, pose another concern. At times, radioactive metal has been found in such waste. Lessons learnt from specific instances have prompted the establishment of radiation monitoring in key locations of large scrap yards. In this context, an apparent irony is evident. Invariably, there is monitoring of incoming goods for potential radioactive contamination by the ports in any country. However, there is little monitoring of outgoing cargo at most ports. This issue remains to be effectively addressed. Failure to control radioactive sources at the originating point is the main cause of radioactive waste contaminating traded scrap materials.

6.1.4 Strengthening Measures to Control the Use of Radioactive Sources and to Foster Alternative Technologies

Increasing concerns about the security of nuclear and other radioactive materials have led to calls for additional protection and control measures, especially while dealing with high-activity sources of Category 1 and Category 2. In this context, the utility of exploring and adopting alternatives to the use of radioactive sources needs to be highlighted. It is commendable that efforts and interest continue to grow regarding benefits of applications of ionising radiation, while fostering avoidance of RI-based sources to the maximum extent possible. This strategy can play a vital role in minimising the use of radioactive sources (especially of Category 1 and Category 2) and in increasing their security. Accordingly, international cooperative initiatives and investment of resources under different forums, including the IAEA and WINS, are noteworthy (IAEA December 2018, WINS December 2020). Advocacy of adopting non-RI sources, such as X-rays and electron accelerators, has grown over the past 10–12 years, as alternative options have emerged in important cases, such as external beam radiotherapy for cancer. It may however take time to become mature in some other cases, such as X-ray-based systems for field applications of industrial radiography. Furthermore, alternatives may not be readily feasible for applications such as brachytherapy. More detailed discussion on alternative technologies for specific cases of applications will follow below.

6.1.4.1 Alternative Technologies to the Use of Radioactive Sources—Existing, Emerging, and Under-Development Options

It is important to distinguish between adopting “existing alternative technologies to RI use” and entirely “newly developed, i.e., emerging, alternatives,” or “alternative technologies being developed” to RI use. This is further elaborated in the next sub-sections. An Expert Group Study organised by the U.S. National Academy (NAS 2021) has also identified the areas to be addressed in offering alternative technologies. The summary of the report lists 15 findings and 9 specific recommendations showing the status of alternative technologies and further efforts needed to make them more amenable for adoption. A brief quote from the synopsis of the report encapsulates the key message: “The committee found that alternative technologies do not provide a “one-size-fits-all solution.” This is particularly evident in medical applications across high- and low- and middle-income countries, because of the stark disparities in access to health care and resources.”

6.1.4.2 Medical Application Sources

There are a few non-RI technology options available as sources of ionising radiation for applications in medicine and industry, with some proven to be superior. For example, in cancer treatment, Linac-based radiotherapy systems have been widely used and possess distinct efficacy and safety advantages over systems using ⁶⁰Co sources, popularly known as “tele-cobalt” machines (IAEA and WHO 2021). However, Linac systems require continuous high-quality electric power supply, without fluctuations in voltage and frequency. This has posed a challenge for many developing nations, LMICs, and non-urban areas of some other countries.

Concerted efforts are hence needed to promote development of low-cost, basic-standard, highly rugged Linac EBRT systems—e.g., 6 & 10 MV—for wider adoption and sustainable use in all countries and regions. The point to highlight is that the reluctance to move away from the RI ⁶⁰Co source can be addressed, reiterating the benefits of alternative technologies accruing to both the patients and the country’s healthcare system. The issue to address should be one of the “rugged, basic-standard Linac EBRT systems for routine use” needed in large numbers by numerous countries versus “advanced, expensive Linac systems,” which would be of interest to high-end medical institutions and the promoting industries.⁸ The relevant issue is not “Linac versus tele-cobalt” systems.⁹

This strategy also requires mobilising adequate financial resources, as well as technical and logistical support, to dispose of spent sources of ⁶⁰Co of the tele-cobalt machines (or of ¹³⁷Cs) previously used in many centres. Campaign mode efforts over the next 2–3 years and global cooperation initiatives can help to make this goal reachable.

6.1.4.3 Industrial Application and Research Sources

In the area of industrial radiation processing applications, ⁶⁰Co-based gamma plants and electron Linacs have their own niche areas of application. In general, radiation processing involving continuous operation is better performed using gamma plants, while cases requiring very high-dose rate exposure or different depths of penetration are more suited to EB treatment. There are also certain areas where both can be deployed and this is where the advocacy for adoption of Linac alternative comes into the picture. In the latter case, ⁶⁰Co-based gamma plants continue to hold practical advantages in terms of ease and simplicity of operations, 24 X 7, about 330–350 days per year. This is essential for end-users in medical fields and the food industry. Here, the need for alternative technology involving electron Linacs, popularly called EB systems, warrants further development efforts to offer ease and economy to end-user industry and service providers. Currently, the techno-economic viability of adopting EB technology for all established applications of radiation processing remains another point of concern. The existing gamma plants, i.e., ⁶⁰Co plants, have up to 500 MCi of sources and these plants have more than a few decades of useful life ahead (iiA brochure 2020; iiA white paper 2020; IAEA CN269 2018). Hence a long-term strategy will be needed in this case.

Non-radioisotope technologies have also been developed in recent years to offer an alternative to the use of RI. Support for technology development and simplification and strengthening of X-ray-based systems would encourage its acceptance. End-users, including medical centres, researchers, academia, and national nuclear centres, can be relatively easily convinced of the alternatives’ merits but they may need some support to avoid use of RI sources. One can also cite the need for portable X-ray-based industrial radiography (IR) devices for field applications of IR in this context. Fostering alternatives to RI in this case will involve persuading a highly-competitive, stressed service industry of the alternatives’ advantages. A two-pronged approach to engage end-users is needed here. The practical logistics issues in open-field conditions, such as availability of the required electric power supply for IR practices, will be a considerable challenge in most developing countries and many other nations.

6.1.4.4 Envisaged Areas of Continuity in RI Source Applications

The final group of applications is the case where no viable alternative to RI exists or can be offered. The most important case is brachytherapy (BT) for treatment of certain cancers. This is a crucial wing of radiotherapy of cancer patients, especially cancers in women. The concept of electronic BT, or contact X-ray BT, continues to remain primarily in the realm of research, with limited demonstrations. High-dose-rate (>12 Gy/h) ¹⁹²Ir sources are mostly used in BT systems, which need replacement once every 2–3 months and involve periodic shipments (Table 6.1). The option to use ⁶⁰Co in place of ¹⁹²Ir may help avoid frequent replacement of sources, but may not be applicable or desirable for all BT applications and in all groups of patients, due to the penetrating nature of ⁶⁰Co radiation. For brachytherapy requirements of cancer treatment, RI-based systems are essential and it is not currently possible to replace them with machine sources of radiation. Such use should continue as a needs-based exception, while advocating the use of alternative technologies. Well-established security mechanisms for the radioactive sources should be employed by the end-users, with compliance overseen by the national regulators.

6.1.5 Control of Radioactive Sources—Continuing Challenges and Path Forward

This paper has described the wide use of radioactive sources for vital applications, practice-specific vulnerabilities posing dangers of various magnitude, lessons learnt from events involving radioactive sources, as well as other technology options available for certain applications. Discouraging the use of radioactive sources wherever alternatives are available will be the logical first option. Techno-economic and logistical issues create barriers to this approach, however, and its feasibility varies across issue areas (Ramamoorthy WNU 2019; IAEA—WHO 2021).

In the case of medical applications, alternatives to radioactive sources should be vigorously pursued, highlighting the advantages to patients. Financial support can be secured from large international and philanthropic sources. In the case of industrial applications, by contrast, practical operational challenges are much more severe. The operators in this group are private entities with significant resource constraints; they cannot receive government support. Industry could seek to transition during a longer period, adopting alternatives such as electron accelerators over time. Support for advances in this technology, such as enhancing ruggedness for 24/7 operation, increasing electric power efficiency, and improving reliability of components and sub-systems, will have to go hand in hand. Securing the buy-in of all concerned industrial stakeholders will be essential for sustainable enforcement of controls and security measures in the above-mentioned applications.

Industrial radiography has thousands of operators across multiple regions. This issue is compounded by the relatively low capital investment required to set up a new IR service entity. As earlier discussed, the IR group is the most vulnerable for exploitation by malicious actors (notwithstanding the relatively lower extent of potential harm and panic). Increased use of machine-based IR systems for industrial specimen inspections, except when required to be done in open-field conditions, can help considerably reduce the volume of IR devices and sources in use in the public domain.

The fact that IR service delivery is based on relatively low capital investment has increased the number of players in the field, which in turn has created a high degree of competition. Requiring a substantial deposit from licensees could help to mitigate these problems. IR licensees should also have adequate provisions of their own for secure storage of their devices and sources at all times. Heavy penalties for violations like non-compliance with transport-related requirements for source safety and security could be helpful. Although national laws and practices may impede their implementation, these measures are worth considering in the interest of safety and security.

In the case of high-risk radioactive sources in research and academic centres, appropriate dissemination of risk-related information and inclusive management practices can help ensure that RI sources are not lost over time, when research priorities change or faculty moves to other locations. Similar techniques can be used in the case of large private entities using nucleonic gauges in their industrial processes. One can also target specific areas where large volumes of such gauges are in use and explore options to deploy X-ray-based gauging systems. Appealing to industry leaders and management to adopt this as part of their “responsible corporate practices” could be a worthwhile endeavour.¹⁰

6.1.6 Recommendations

This chapter concludes with two sets of recommendations to improve security around the challenges identified herein. First, it is possible and necessary to move away from using RI sources for external beam radiotherapy (EBRT) of cancer patients. This can be achieved by concerted efforts to build consensus around a standard, simple system for basic routine EBRT. Such efforts would seek large-scale deployment, including in locations with resource constraints of infrastructure, as well as to facilitate all aspects of transition from the old tele-cobalt machines. The partnership of industry is crucial in this context. Further, harnessing synergies among relevant entities, such as cancer care professionals and healthcare authorities, Linac system industries, professional entities like IARC, and inter-governmental organisations like IAEA & WHO, along with the support from international initiatives to strengthen nuclear security, will be required. Global philanthropic aid available for healthcare can be leveraged for this purpose. A time-bound action plan (2–3 years) and implementation mechanism should be attempted, with the lead entity being determined through consensus among key stakeholders.

The second set of recommendations is related to the inevitable requirement of RI sources for certain vital applications, and the possibility of fostering adoption of alternative technologies to RI use for other applications wherever possible.¹¹ A transparent stakeholder process should clearly identify cases where alternatives to RI use are not feasible. Simultaneously strengthening the radioactive sources in these systems against theft and sabotage through design, shielded housing, tracking, physical protection, etc.), against theft and sabotage, should be given priority.

Another potential strategy would be supporting the deployment of rugged alternative technologies in place of equipment such as blood irradiators, research irradiators, and radiography devices containing RI sources. This would enable end-users to consider transition to non-RI-based options for applications wherever possible. The question of how to make such a transition adequately attractive for the licensee or employer delivering radiation-based services has to be addressed. Persuading industry to demonstrate the utility and reliability of offer alternative equipment and systems at IAEA labs in Seibersdorf can be an option.

The duration for these pursuits will be much longer than in the case of medical Linacs; a timeline of 5 years may be worth considering as a target. Bringing together all relevant stakeholders may pose challenges, due to commercial interests, and concerns regarding the techno-economic viability of new options. Nonetheless, it would be worthwhile to strive for a paradigm shift.

6.2 A U.S. Perspective

• Christopher Boyd &
• Anne L. Willey 

Christopher Boyd, Anne L. Willey

In the 20 years that have transpired since the terrorist attacks on September 11, 2001, there has been a growing awareness of the potential for the pernicious use of sealed sources—radioactive materials meant to be kept permanently sealed in a capsule or bonded and in solid form (IAEA). These materials emit excess energy (radiation); one of the forms this energy takes, gamma rays, is often used for life-saving treatments and critical infrastructure applications. However, if these sealed sources fall into the wrong hands, they can be deployed as weapons and cause serious harm. Concerns over the use of sealed sources in the making of radiological dispersal devices (RDDs), also known as “dirty bombs,” have led to a re-evaluation of approaches to radiation security, especially regarding soft targets such as healthcare organizations, commercial and federal operations, and institutions of higher learning.

For the last 20 years, regulatory bodies at national, regional, and international levels have developed far-reaching policies and procedures to mitigate security risks associated with sealed sources. Enhancing security measures, while sometimes effective in reducing opportunities for malicious use, requires a permanent commitment to managing risk. A fundamental problem with this risk management approach is that it is very resource-intensive—not only in economic terms, but also in terms of technology, human power, and political capital. Risk management requires, at a minimum, continued upgrades in physical security controls, increased coordination with law enforcement at all levels of government, as well as expansion of personnel training, screening, and assessment programs.

Risk mitigation also can require cultures of safety and security within the nuclear enterprise and beyond IAEA. While very important and desirable, safety and security cultures must ultimately rely on human factors, such as attitudes, beliefs, and behaviors. These factors are often resistant to change and difficult to control.

Stakeholders in all sectors have come to recognize these problems with risk mitigation. They have concluded that permanent risk reduction approaches, which promote adoption of alternatives to sealed sources, are preferable. Replacing sealed-source devices with alternative technologies that do not require the same level of protection and vigilance provides the most effective and efficient means of increasing security.

Where viable alternatives exist (see Non-Isotopic Alternative Technologies Working Group 2019), the adoption of these alternative technologies should be encouraged. Denmark, France, and Norway, supported by strong legislative mandates, embraced a risk elimination approach and replaced all cesium blood irradiators by 2016. Japan replaced 80% of its cesium blood irradiators by 2017. Finland, Switzerland, and Sweden have strong programs promoting the adoption of alternative technologies, which include requiring justification for seeking approval for acquiring new gamma devices.

Until recently, the United States had fallen behind other nations’ efforts to replace cesium irradiators. This situation was due at least in part to the complexities of the country’s governmental framework, in which regulations and interests at the federal (nation-wide) level overlap and occasionally conflict with those of its states (regions/provinces). However, intensifying concerns over security threats posed by malicious actors have led to a steady increase in support for alternative technologies. Indeed, the US offers an interesting case study in how a risk elimination approach targeted to open, low-security environments can become an integral part of a national risk management strategy. The United States’ success in instituting a voluntary cesium irradiator replacement program that allocates financial and logistical resources to facilitate acquiring the new technologies, as well as removing and disposing of the sealed sources in a secure way, provides a model that could be emulated by other governments who wish to permanently eliminate risk but cannot secure a legislative mandate to do so.

This chapter begins by placing the regulatory landscape for sealed sources in the United States in both a historical perspective and an international perspective. Section 6.2.1, “Overview: the Regulatory Framework in the United States,” discusses the emergence in the United States of the “risk management” approach to the regulation of sealed sources, in the context of the Cold War and also the “War on Terror.” Section 6.2.2, “Challenges Within the Framework,” highlights limitations and conflicts in current regulation, arising in part from the structure of the United States government, where federal, state, and occasionally cities can share jurisdiction over sealed sources. Section 6.2.3, “An Emerging Consensus,” discusses the advantages of adopting a “Public Health” approach that reduces the reliance on radioisotopic technologies, especially in low-security settings, in favor of alternative technologies. The authors discuss one such program developed by the U.S Office of Radiological Security: The Cesium Irradiator Replacement Project (CIRP). The program offers meaningful financial and logistical support to stakeholders who voluntarily agree to adopt non-radioisotopic technologies. It has had great success in replacing high-activity radiological devices located in open, low-security environments, particularly within healthcare and research settings.

The paper concludes that seeking permanent threat reduction is both the most forward-looking and fiscally responsible approach to radiological materials management. Eliminating sources of risk in a categorical way produces better outcomes and greater safety than managing these sources of risk. Government regulation should facilitate the process of replacement and support institutions and organizations that are willing to transition to technologies that do not pose terrorism risks. During the interim period when regulatory and/or legislative direction has not been established, government agencies responsible for the regulation of radioactive sources should promote voluntary replacement as the preferred permanent risk reduction strategy. Strategies based on the long-term management of security risks should be adopted only when the potential for high-consequence events cannot be eliminated due to the absence of feasible alternatives to sealed-source devices.

6.2.1 Overview: The Regulatory Framework in the United States

The current regulatory landscape for radioactive materials in the United States is complex, due to the overlapping jurisdictions created by state and federal/national agencies and legislation. This was not always the case and it is instructive to examine legislative actions and social dynamics that shaped how radiological security in the United States evolved.

6.2.1.1 Federal Regulators: The Nuclear Regulatory Commission

The Atomic Energy Act of 1954, as amended in 1959, is the law that regulates civilian and military uses of nuclear materials. The law ended the federal government monopoly over nuclear power, allowing for the participation of the private sector in the expanding nuclear industry and shifting the federal role to one of promotion and regulation of private enterprise (Yates 1976, 399). All responsibility for both military and civilian uses of nuclear materials and technology fell under the control of the Atomic Energy Commission (AEC). This agency was put in charge of regulating both military and civilian uses of nuclear technology.

Jasper (1996, 31) claims that “the AEC interpreted its role less as regulation than as promotion of the new technologies.” This posture was shared by many politicians and policy makers outside the AEC and led to the rapid growth of the nuclear industry during the 1960s and early 1970s. Nevertheless, many citizens, influenced by growing environmental concerns, remained deeply skeptical of nuclear power. Quirk and Terasawa (1981, 833) describe the situation as follows:

But even during the boom years for nuclear power, controversies were growing concerning almost every conceivable aspect of the industry, from the mining of uranium through reactor operations to disposing of nuclear wastes. Environmentalists and other intervenors argued that nuclear power was inherently unsafe, and that regulation of the industry was ineffective, so that the long run consequences of an economy powered by nuclear energy would be devastating.¹²

Much of the concern focused on a perceived conflict of interest in the AEC’s dual role as promoter and regulator. Factors such as wildly inaccurate predictions about cost-savings (Jasper 1996, 29) and lengthening approval times for the licensing of new projects (Quirk and Terasawa 1981, 834) contributed to weakening governmental support for nuclear energy, which in turn further undermined public confidence. The situation was only made worse by the AEC’s resistance to addressing environmental concerns (Greenberg 1996). In 1974, Congress addressed the perceived conflicts by creating the Nuclear Regulatory Commission (NRC) and entrusting it with regulatory functions over civilian nuclear technology, including source materials and the devices that rely on them. It is important to note that this agency was not given an official role in the promotion of nuclear technologies,¹³ or in the regulation of mining.¹⁴

Rules governing use, access, security, transportation, storage, and decommissioning of sealed sources and byproduct materials in the United States are contained within the Code of Federal Regulations (CFR) title 10 parts 25–40. Following the terrorist attacks on September 11, 2001, additional security measures were instituted for Category 1 and Category 2 materials, which are contained within 10 CFR part 37. Other enhancements include a National Source Tracking System (NSTS), created to trace high-risk radioactive sources from the time they are manufactured or imported through the time of their disposal or export, or until they decay enough to no longer be of concern, as well as a National Sealed Source and Device Registry (NSSDR), which contains summaries of engineering and radiation safety evaluations of sealed sources and devices conducted by both federal and state regulators under the conditions of their possession and use. NRC has resisted including Category 3 materials in any of these additional measures (GAO 2019, 5).

6.2.1.2 State-Level Regulation: “Agreement State” Compacts

The Atomic Energy Act of 1954, as amended in 1959, provides a statutory basis under which the NRC relinquishes to the States portions of its regulatory authority, allowing them to license and regulate health and safety impacts of sealed sources and devices. The mechanism for the transfer of NRC's authority to a State is an accord signed by the Governor of the State and the Chairman of the Commission of the AEC (later the NRC) in accordance with Section 274b of the Act. States that enter into such a compact become “Agreement States.” This legislation recognized that localized health and safety risks associated with byproduct material were similar to other public health risks managed by local governments, and there was not a national interest requiring federal control. If specified, the compact can include a commitment to enforce on the NRC’s behalf orders and requirements related to common defense and national security (Section 274i). In the later instance, the federal agency was not relinquishing authority, but merely delegating a duty. If a State did not enter into such an Agreement under any terms, all regulatory authority was left with the AEC/NRC.

Currently, the process of becoming an Agreement State takes approximately four to five years. Once the petition is approved, the NRC Management Review Board assesses each Agreement States’ performance every four years to ensure that the state’s program is adequately performing its regulatory obligations. The mechanism used by the NRC to oversee states is the Integrated Materials Performance Evaluation Program (IMPEP). The organizational structure of IMPEP teams nominally allows for Agreement State input. In practice, however, NRC staff outnumber Agreement State personnel (NRC Office of Inspector General). The NRC maintains reassertion authority in the case of accidents or emergencies, and there is a probationary period during which an Agreement State can lose its authority. To date, 39 out of 50 states have joined the Agreement State program and one more is in the process of doing so.

The primary mechanism to organize, support, and facilitate the interactions between the Agreement States and the NRC is the Organization of Agreement States (OAS). The OAS is a private, not-for-profit professional society for the Agreement State radiation control program directors and their staff. The OAS is a voluntary organization, has no full-time staff, and is funded primarily through grants from the NRC. OAS has taken an active role in attempting to minimize conflicts between individual states and the NRC and pursuing a role for states in matters that have come to be seen as part of national security (Squassoni et al. 2014, 17). However, the OAS has limited administrative capacity. It relies on state regulators to volunteer staff, otherwise charged with regulatory responsibilities, to orchestrate engagement with the NRC’s full-time administrative, legal, and policy planning personnel. This imbalance in administrative capacity clearly complicates dialogue between the two categories of regulators.

6.2.1.3 Agreements with the Armed Forces

The NRC’s regulatory authority over sealed sources extends to devices under the jurisdiction of the Armed Forces. It delegates its authority to these agencies through a Master Materials License (MML). These licenses are designed to account for the diversity of sites, locations, and materials (byproduct, source, and/or special nuclear material) that might be under the jurisdiction of the armed forces (NRC, Master Materials License). Each military branch has its own centralized radiation control program responsible for ensuring regulatory oversight and compliance with the terms of the license. Under the authority of the MML, these centralized radiation programs can issue permits for the possession and use of sealed sources listed on the MML. In order to receive the MML, the licensee must agree to program inspections every two years. The NRC also has the authority to independently inspect permit holders.

6.2.2 Challenges Within the Framework

Edwards (2016, 151) argues that while the current radiation regulatory scheme has served the country well, the framework nevertheless “must periodically evolve and adapt to ensure that public health, workers, and the environment are properly protected in view of accepted societal values and the advance of science, technology, and medical practices.” In the United States, conflicts over the proper allocation of power between the federal government and the states are not uncommon. State law is not permitted to contravene federal law. At the same time, there is a widely held belief that federal laws should not encroach on matters best dealt with at the local level, and that all matters not explicitly regulated by federal law fall under state jurisdiction. State laws are necessarily complementary to federal regulation and there is substantial coordination between federal and state regulators in all manner of directives, oversight, and enforcement. Nevertheless, when it comes to regulating radioactive materials, including sealed sources, the stakes involved in any perceived conflict are significantly higher. Several factors are involved in making the dynamics of collaboration between federal and state regulators particularly fraught (see Aron 1997; Jones 2019).

Below, we will focus on challenges that arise within the Agreement State framework. Edwards (2016, 153) proposes several broad criteria that regulators should keep in mind when crafting directives and guidance. Among them is to ensure that regulations are protective yet flexible, that requirements are clear, and the directives are forward looking. We will first consider whether current regulations are sufficiently forward looking and whether they strike the appropriate balance between protection and flexibility when it comes to meeting specific local security needs within a nation-wide regulatory scheme. We will then consider whether the language used in creating compliance criteria is sufficiently clear and specific.

6.2.2.1 Compatible vs. Identical Regulations

Agreement States are expected to issue regulations that are “adequate and compatible” with those issued by the NRC (NRC “Security Orders and Requirements”). NRC’s rigid interpretation of compatibility means that in practice they expect state regulation to be identical to their own Greer. This can lead to significant disagreements between state and federal regulators. Despite heightened security concerns relating to RDDs, states felt strongly that they continued to be the best option in regulating the security of sealed sources (GAO 03-804, 1). Furthermore, the vast majority of Category 1 and Category 2 licenses are regulated by the 39 Agreement States. Nevertheless, despite the NRC’s dwindling licensing responsibilities and the revenues tied to them,¹⁵ its administrative and policy resources dwarf those of individual states. As a result, the NRC exercises significant control over both policy dialogue and regulation changes.

Currently, the NRC considers regulations that are more rigorous than its own to be incompatible with its requirements (NRC 2018).¹⁶ This poses unique challenges for states with a high security risk profile tied to high population densities, their role in national or international economies, or simply the concentration of sealed sources located in low-security environments. States wishing to challenge IMPEP reviews must contend with a protracted process that can become administratively and financially burdensome. Mistrust between State and Federal regulators is heightened when federal decisions appear unduly influenced by stakeholders seeking a unified regulatory environment that facilitates the achievement of their commercial or professional interests, rather than promoting relevant health and safety concerns at national, regional, and local levels (Rojas-Burke 1992: 28; see also Jones 2019).

As the balance of direct regulatory activity for radioactive materials has shifted to the Agreement States, it could be argued that one of the NRC’s primary roles has shifted to “overseeing the overseers”—the Agreement States. Given the imbalance of power between States and the NRC, the threat of increased audit schedules and negative findings that can result from the IMPEP process can further suppress open and honest communication between federal and state regulators. This makes the IMPEP process less a dialogue about best practices and more of an instrument to bring Agreement States into alignment with NRC policies and procedures. Establishing minimum national standards need not preclude states from addressing their own unique health, safety, and security risks.

6.2.2.2 Prescriptive vs. Performance-Based Criteria

The NRC takes a performance-based approach to determining regulatory compliance (Medalia 2012, 26). Performance-based regulations focus on the ultimate outcome or the effect of the regulation and are designed to allow stakeholders greater flexibility in how they comply with the law, as long as the ultimate intent of the law is met. A prescriptive approach, as the name suggests, dictates the exact steps and procedures that must be followed in order to be considered in compliance. When it comes to dealing with safety measures, a performance-based approach can be frustrating to some state regulators who would prefer to provide more concrete guidance to licensees about what mechanisms and systems are likely to be most effective. It can also be frustrating to the licensees themselves, who may be uncertain as to what measures are sufficient to meet the standards.

The use of highly subjective terms contributes to the problem. NRC regulations require licensees to ascertain that persons with unescorted access to Category 1 and Category 2 materials are “trustworthy and reliable.” It is left to HR personnel hired by the licensees to see that those standards are met. Decisions are expected to rely on routine information gleaned from law enforcement databases, previous employers, and character references. Psychological assessments are not included in review materials, and individuals are only re-evaluated every 10 years. Medalia (2012, 8) suggests the current standard can result in subjective judgements and inconsistencies in hiring practices.

A recent incident underscores the risks of relying on licensees’ hiring practices and the potential for insider threats to result in the malicious use of radioactive materials. In 2019, Jared Atkins, an employee of an engineering firm who had been granted unescorted access to Category 2 materials, began experiencing a mental health crisis. He decided to steal three radioactive devices from his workplace in Arizona. Once in possession of the devices, he communicated to family and coworkers his intention to release the materials at a popular shopping area. Authorities were not aware of the theft until those who he had messaged about his malicious intentions contacted law enforcement. Catastrophe was only averted because the person ultimately changed his mind (Stern 2021; see also NRC 2019).

The safety regulations laid out in 10 CFR Part 37 require licensees to “provide reasonable assurance of the security of Category 1 or Category 2 quantities of radioactive material by protecting these materials from theft or diversion” [emphasis added]. The regulation does not define what “reasonable assurance” would be. While it does prescribe the creation of security zones around Category 1 and Category 2 materials, commonplace security measures such as key card, passcode, and biometric technology systems are not required. Alarm systems to detect and record non-scheduled or after-hour removal are also not required. In the above incident, a standardized personnel reliability program (PRP) for staff with unescorted access to Category 1 material may have identified the insider threat prior to commission of the crime. Indeed, the Department of Defense requires further regulation of the reliability of its workforce than its civilian counterparts through the implementation of PRP in DoD Instruction Manual 5210.42 Nuclear Weapons Personnel Reliability Program (PRP).

This lack of prescriptive regulations might be explained by the fact that NRC gears the safety standards toward limiting the risk of short-term health exposures. However, when dealing with RDDs, it seems reasonable to also take into consideration health risks and societal costs relating to a large-scale evacuation, and the extremely high costs of environmental clean-up. Furthermore, the mental health effects of surviving an RDD attack should also be considered. Indeed, in the case discussed above, the economic and mental health impacts would have been felt long after the immediate health impacts were addressed and palliated.

Recent studies suggest that the deployment of an RDD in an urban center such as New York City would not only significantly impact the regional economy but also impact the United States Gross National Product (GAO 2019). Another recent incident makes abundantly clear that these predictions are no longer theoretical. In 2019, a vendor in the process of decommissioning a cesium irradiator in Washington State breached the sealed source, releasing an estimated 1 curie of cesium 137 and contaminating the seven-story research facility. Two years later, the costs of environmental remediation and reoccupation—for 1 curie in a single, modestly-sized structure—have soared to over $100 million. This staggering sum makes it abundantly clear that a continued focus on short-term health effects is insufficient¹⁷ and calls for a reassessment of the economic models used to evaluate the impacts of a cesium or radioactive material release in a major urban center.

In summary, the performance-based approach, while offering licensees flexibility in meeting the intent of the regulation, has significant limitations when dealing with the dangers posed by malicious or even accidental release of sealed-source materials. In our current national and global political climate, this is a risk that should not be underestimated.

6.2.3 An Emerging Consensus: Permanent Risk Reduction

The regulatory approaches to security discussed thus far focus on risk management. Such approaches necessarily assume high costs for securing sealed-source devices. These include not only one-time investments in equipment and infrastructure, but also recurring expenses such as licensing fees, liability insurance, security personnel, and administrative overhead. We propose instead to take a “public health” approach o security, prioritizing risk prevention and elimination, and adopting mitigation strategies only when elimination is not feasible. Such an approach calls for removing high-activity radiation materials from low-security, open access environments such as medical and healthcare facilities, research centers, and universities. Stakeholders at local, regional, national, and international levels are increasingly recognizing that reducing the use of sealed-source devices whenever alternatives are available is the most effective and financially sound security strategy.

The following section focuses on the significant success of a federal program that promotes permanent risk reduction by incentivizing organizations to exchange their sealed-source devices for comparable ones that use alternative technologies, such as X-rays. We also present case studies showing how federal, state, and local regulators collaborated with non-governmental organizations to promote large-scale adoption of this strategy.

6.2.3.1 The Cesium Irradiator Replacement Project (CIRP)

Given that the ability of Agreement States to establish prescriptive security measures as part of the “reasonable assurance” provision is limited, many states have sought to address structural security gaps through consensus-building mechanisms and voluntary programs provided by the Department of Energy’s (DOE) National Nuclear Safety Administration (NNSA). Congress created the NNSA in 2000 as a semi-autonomous agency within the Department of Energy (DOE) responsible for reducing the global danger from weapons of mass destruction, among other critical missions. Though the NNSA has no regulatory authority over civilian uses of sealed sources, its role in counterterrorism and nuclear non-proliferation lent itself to a concern with the safety and security of radioactive devices both nationally and internationally. Beginning in 2004 with the Global Threat Reduction Initiative (GTRI), and continuing with the creation of the Office of Radiological Security (ORS), NNSA became involved in the recovery of orphan and disused sources and enhancing security measures for high-activity radioactive materials both within and beyond U.S. borders.

While it held no regulatory authority, ORS became deeply involved in strengthening security protocols after the September 11 attacks. ORS strengthened collaboration between state radiological regulators, licensees, and local law enforcement agencies, offering workshops on responses to radiological theft alarms. It also worked directly with licensees to improve their security systems, instituting a voluntary program that provides protection upgrades, guidance, and training to enhance the security of high-activity radioactive sources. ORS also addressed the problem of disused sources, removing, and disposing of them at no cost to the licensee.

Over time, the security efforts of the ORS and the NNSA evolved from managing security risks to promoting permanent risk reduction. ORS now describes its mission as consisting of three “pillars”: protect radioactive sources used for medical, research, and commercial purposes; remove and dispose of unwanted or abandoned sources; and reduce the reliance on highly active radioactive sources by encouraging development and use of alternative technologies such as X-rays whenever possible. Within its “Reduce” mission, the Cesium Irradiator Replacement Project (CIRP) offers a particularly successful model for promoting the voluntary adoption¹⁸ of alternative technologies. This project has not only resulted in significant permanent risk reductions but encouraged important technological innovation in health services and in medical research.

Established in 2015, CIRP aims to persuade eligible U.S. organizations to voluntarily participate in the program by educating them on available alternative-technology devices and providing a wide range of resources: These resources include audit tools that support organizations in assessing the feasibility of transitioning to alternative technologies; access to experts who can answer questions about the transition to new technologies; opportunities for discussion with peers also considering this option; as well as compatibility studies between different technologies. Importantly, CIRP provides financial support to help fund the purchase of alternative technologies and arranges for the removal of disused gamma devices at no cost to the user. The program has had a significant impact in creating an industry-wide consensus about the benefits of X-ray devices in blood irradiation, which will be crucial in helping the United States meet its goal of eliminating the use of blood irradiation devices that rely on cesium chloride by December 31, 2027, as laid out by Congress (H.R. 5515 2018; Garrison et al. 2018).

6.2.3.2 Collaborations with Diverse Stakeholders

During the first four years of its existence, CIRP was responsible for replacing 20% of the gamma irradiators in the United States, a rate of roughly 40 irradiators per year. In addition, CIRP has commitments from licensees to replace another 20% of the inventory by 2023. This stunning success was achieved in large part through collaboration with the DOE/NNSA National Laboratories, state regulators, university systems, private sector stakeholders, and non-governmental organizations. The National Laboratories expanded their role from offering voluntary security enhancements to providing expertise in alternative technologies. The DOE/NNSA National Laboratories also expanded their capacity for removing and disposing of disused sealed sources at no cost. State regulators and non-governmental organizations also help coordinate outreach to commercial, public, and nonprofit users. CIRP supported Vitalant, the largest independent, nonprofit blood services provider in the United States with offices located throughout the country, as it committed to replace all its cesium blood irradiators with X-ray devices. Vitalant’s example has been crucial in gaining the trust from other providers of blood irradiator services, who have come to appreciate that X-ray technology not only offers benefits in terms of reducing regulatory and security burdens, but also provides gains in quality and quantity of the blood supply.

CIRP’s collaboration with the Nuclear Threat Initiative¹⁹ (NTI) also deserves detailed discussion, as it provides a successful model for using consensus-building strategies to gain the support for the adoption of alternative technologies from a wide range of stakeholders. In New York City, NTI supported the local regulator²⁰ in convening discussions between ORS officials and representatives from universities, healthcare and research institutions to help them see beyond their individual organizational needs and move towards a city or region wide, public health understanding of risk reduction. Participants took the information back to their institutions, where they engaged in further consensus-building among researchers, radiological security officers, and administrators, allowing for open discussion of the promises and challenges of X-ray technology. In the end, these efforts will result in the replacement of 75% of the cesium irradiators within the city (Kamen et al. 2019; Iliopulos and Boyd 2019, 9–12). CIRP also collaborated with NTI to successfully obtain commitments from the University of California system to replace 90% of its cesium irradiators (MacKenzie et al. 2020; Iliopulos and Boyd 2019, 13–16). In a report published in 2019, NTI lists important lessons that can be learned from the success of these replacement endeavors. Recommendations include identifying and fostering local advocates and support networks; making information on alternatives to sealed-sources devices readily available; seeking consensus for the change from stakeholders using cesium devices within and among institutions; and increasing funding at federal levels to support the efforts (Iliopulos and Boyd 2019, 17, 20–23).

ORS is also engaged in international collaborations. Their focus is on reducing the reliance on radioactive sources used in medical, industrial, and commercial applications. Their efforts involve providing a range of financial incentives and support to stakeholders in partner countries who are interested in voluntarily replacing sealed-source devices with non-radioisotopic alternatives. It also works to repatriate radioactive sealed sources that originated in the U.S. and supports partner country efforts to remove disused sources to a secure location.

6.2.3.3 Elimination of Nuclear Threat Networks to National Security

The U.S. Federal government is heavily invested in the detection and elimination of materials capable of creating a nuclear or radiological threat to the American public and international partners. The Defense Threat Reduction Agency (DTRA) within the Department of Defense (DoD) acts to consolidate, secure, and eliminate weapons-usable radiological and/or nuclear materials abroad in efforts to prevent these devices from becoming weaponized by State or Non-State actors. These endeavors have been successfully accomplished by codifying umbrella agreements between the U.S. Department of State and foreign governments establishing mutual cooperation towards eliminating the nuclear and radiological threats posed by high-threat regions. Leveraging these international agreements, DTRA has focused efforts on the detection and interdiction of nuclear materials smuggling in these regions by providing radiological detection equipment, security training, logistics infrastructure, and nuclear dismantlement technology. These programs have shown particular success in threat reduction and elimination in nations such as Kazakhstan and Ukraine, which were historically inundated with dangerous materials from old nuclear reactors and weapons testing from the former USSR nuclear programs.

6.2.4 Conclusion

This chapter has highlighted how an effective regulatory framework must incorporate national, regional, and local levels. This framework must be based on fair collaboration practices, open channels of communication, and explicit division of responsibilities. Certainly, the advantages of having minimum nation-wide standards are indisputable. However, settling for only minimum requirements creates gaps in the regulatory regime and makes it difficult for local officials to fully meet the distinct needs of their populations. Federal regulators should value the knowledge that their state partners bring to discussions and should acknowledge that local and regional threat levels might require enhanced security protocols. While in some instances that might create a more complex regulatory landscape for licensees, it will ultimately yield benefits in terms of safety and preparedness.

We also made the case for including prescriptive measures, such as personnel reliability programs, within regulatory frameworks, to avoid inconsistencies in oversight and compliance. The two recent incidents we discussed illustrate the dire consequences of such security gaps. As an alternative, we presented an example of a federal program that achieved security enhancements through fostering cooperation between diverse stakeholders, including offering financial and technical support.

Finally, we strongly recommended the creation and/or expansion of programs that facilitate the replacement of sealed-source devices. There is no question that high-activity radioactive materials provide many advantages to the industries that use them. Nevertheless, when housed in low-security, open environments, these advantages can be offset by the serious challenges their protection and potential malicious use pose. The dangers of accidental or intentional release of high-activity radiological materials are no longer hypothetical, nor are they decreasing. Thankfully, we currently have viable alternatives to many sealed-source devices, and research and development continues to offer promising new advances in these technologies.