ICRU

The International Commission on Radiation Units and Measurements (ICRU) is an international non-governmental organization that develops and promotes standardized quantities and units for the measurement of ionizing radiation. Its work aims to harmonize dosimetry terminology, measurement methods, and data interpretation across research, clinical practice, and radiation protection.

ICRU was established to provide internationally accepted definitions and procedures for quantifying radiation, with its work published in a series of ICRU Reports. These reports define dosimetric quantities, calibration methods, and uncertainty assessments, and cover topics from basic quantities such as absorbed dose and kerma to protection-oriented measures like dose equivalents and effective dose. The organization collaborates with scientists and clinicians across disciplines to ensure that measurements are comparable worldwide.

The ICRU’s recommendations and data inform international standards and regulatory frameworks. Its work is widely used by other international bodies, including the International Commission on Radiological Protection (ICRP) and ISO, and it underpins clinical protocols in radiology, radiation therapy, and nuclear medicine, as well as safety practices in industrial radiography and research.

Governance and operation are conducted by an international group of experts who contribute through specialized working groups. A rotating secretariat coordinates the production, dissemination, and revision of ICRU Reports, maintaining an ongoing effort to refine and update dosimetric quantities in response to technological advances and new scientific understanding.