Since its inception in 1925, the principal objective of the ICRU has been to provide guidance and recommendations in the areas of radiation science (e.g., radiation therapy, radiation protection, radiology, radiobiology, etc.), and the compilation of data important to these fields aiming at facilitating scientific research, education, and other activities including industrial applications of ionizing radiation.
A sphere of importance is the availability and consistency of terms and definitions compiled throughout ICRU reports over many years. Traditionally, the inclusion of glossaries that provide terms and definitions was not mandated, although they do exist in most of the ICRU reports. At the same time where they do exist, the report glossaries often differ regarding format and style, making retrieval and use challenging. For example, in some reports, the glossaries lack definitions and only comprise spelling out of abbreviations or acronyms. Definition of terms may also vary across reports, although this can sometimes be explained by the context in which they were employed. Moreover, some terms are outdated or less relevant to contemporary radiation science or the overall work of the ICRU. Thus, scientific or medical terms of a basic nature (e.g., names of regular medical conditions or anatomic regions, treatment procedures, or regular statistical terms used for straightforward data analysis, etc.) exist in some ICRU reports, along with multiple variations of some terms with similar but not identical definitions.
In consideration of the need for global consistency of radiation quantities, units, terms, and definitions, and to facilitate and support its present and ongoing work, the ICRU undertook a review of terms and definitions and assembled this glossary of contemporary terms. Although the glossary is relatively extensive, it is not intended to be comprehensive with respect to all prior ICRU reports, nor all radiation science and medicine. Other glossaries, such as those provided by the International Commission on Radiation Protection (ICRP) and the International Atomic Energy Agency (IAEA), provide additional radiation-related glossary entries. With this in mind, a report committee was tasked with initiating a project to consider the purpose, criteria for inclusion or exclusion of glossary entries, the format of the glossary, and a process to create the glossary in this report. This involved a proposal to retrieve and compile terms and definitions and a means of approval and refinement for inclusion in this report.
The deliberations and procedures are outlined below, followed by the final approved terms and definitions in alphabetical order that comprise the glossary represented by this ICRU report.