Radiation shielding meaning

Radiation shielding is the engineered use of absorbing materials (such as lead, concrete or water) placed between a source of ionising radiation and people to attenuate dose and reduce exposure. It is not a defined statutory term, but a widely used expression across radiation protection law and guidance. It underpins compliance with duties to restrict exposure and keep doses as low as reasonably practicable (ALARP) or achievable (ALARA). In Great Britain this duty arises under the Ionising Radiations Regulations 2017 and HSE/ONR guidance; in Northern Ireland under equivalent regulations; and in Ireland under legislation implementing the EU Basic Safety Standards, overseen by the EPA/HSA. Usage is broadly consistent across all four jurisdictions. Key legal features and use: shielding is a primary engineering control identified in radiation risk assessments; it must be specified and verified in the design and siting of controlled and supervised areas, plant and enclosures (for example, radiotherapy bunkers, X‑ray rooms, hot cells); and incorporated into the design of transport and waste packages. Adequacy of shielding is scrutinised when setting dose constraints, planning or modifying facilities, granting or varying licences and permits, and during inspections or incident investigations. Dutyholders must evidence that shielding is suitable and sufficient, maintained, and integrated...