1INTERNATIONAL ATOMIC ENERGY AGENCY, Radiation Protection and the Safety of Radiation Sources, Safety Series No. 120, IAEA, Vienna (1996).

2The term ‘regulatory body’ is used to cover all types of regulatory infrastructure, including systems having single or multiple authorities at the national level only and federal systems where authority is distributed across the relevant regional, provincial or State jurisdictions. ‘Regulatory body’ is synonymous with the term ‘Regulatory Authority’ that was used in some earlier IAEA publications, such as the BSS.

3In this Safety Guide, the term ‘user’ is sometimes used as an alternative to ‘principal party’ (see para. 2.6) to avoid awkwardness of expression. ‘Principal party’ is always used when it is the subject of a recommendation (a ‘should’ statement).

4A ‘legal person’ is an individual or organization recognized as an entity for legal purposes (see the BSS [17]).

5Where the word ‘source’ is used in this Safety Guide without qualification, or in the term ‘radiation source’, it is to be taken to mean either a radiation generator or a radioactive source, depending on the context.

6Radiation sources are often built into devices that direct, filter, scatter or otherwise affect the radiation emitted. Such devices are covered by this Safety Guide to the extent that the source is an integral part of a device; the safety of devices more generally is dealt with in other IAEA publications. In this sense, the word ‘source’ is used in this Safety Guide to mean ‘source and device’, as appropriate.

7Reference [20] contains interim guidance only. Further publications dealing with security matters are issued in the IAEA Nuclear Security Series.

8The phrase ‘security for safety’ is used in this Safety Guide to convey this limited meaning

9The term ‘nuclear material’ is defined in the Convention on the Physical Protection of Nuclear Material [21] as “plutonium except that with isotopic concentration exceeding 80% in plutonium-238; uranium-233; uranium enriched in the isotope 235 or 233; uranium containing the mixture of isotopes as occurring in nature other than in the form of ore or ore-residue; any material containing one or more of the foregoing”.

10The term ‘orphan source’ refers to a radioactive source that is not under regulatory control, either because it has never been so, or because it has been abandoned, lost, misplaced, stolen or otherwise transferred without proper authorization.

11The BSS [17] state (para. 1.6) that: “The principal parties having the main responsibilities for the application of the Standards shall be: (a) registrants or licensees; and (b) employers.”

12An IAEA Safety Requirements publication covering safety assessment and verification is in preparation.

13A severe deterministic effect is one that is fatal or life threatening or results in a permanent injury that decreases quality of life [23].

14Further guidance on the safety of devices is to be provided in other IAEA publications at present under development, and separate guidance on the design and manufacture of sources to address security objectives is planned.

15Attention should also be paid to the possibility of a ‘dark current’ (when the power to the electron source is off but a high voltage remains on the anode) and of activation of accelerator components in the case of very high energy particle accelerators.

16Guidance on engineering controls for the security of sources will be provided in other IAEA publications.

1This annex provides an illustrative example compiled from expert advice and multiple sources. ‘Should’ statements in the body text and appendices of a Safety Guide express recommendations, indicating an international consensus that it is necessary to take the measures recommended (or equivalent alternative measures) for complying with the requirements. However, an annex is not an integral part of the standard, and where the word ‘should’ is used in this annex, it does not have this special meaning. In this annex the word ‘should’ is used in its usual dictionary sense only.

1Publications under development include Safety Reports on industrial radiography, radioactive gauges and well logging using radioactive sources.

1Note that figures are given to an unrealistic degree of precision in these illustrative calculations in order to show the working. In practice, a single significant figure is likely to be appropriate.