U.S. drops a core radiation safety rule as global reforms near

U.S. Department of Energy drops ALARA, challenging global radiation safety norms as reforms and debates intensify.

The linear no-threshold (LNT) model and the ALARA principle have served as the conceptual and operational foundations of the global radiation protection framework for many decades.

The LNT model is a risk estimation framework that says any amount of ionising radiation, no matter how small, carries some risk of causing harm, especially cancer. In other words, there is no threshold below which radiation is considered completely risk‑free. And the risk increases linearly with dose.

ALARA, short for “as low as reasonably achievable”, is the operational philosophy of radiation protection. ‘Reasonably’ is the most important condition. The philosophy balances safety with feasibility, cost, and societal need, and its aim is to improve continuously, including better shielding, administrative procedures, and training.

Thus in practice ALARA aims to reduce unnecessary exposure using engineering controls and encourages a safety culture.

Unfortunately, when these principles are misapplied, as they have often been, they create a baggage of woes. The International Commission on Radiological Protection (ICRP) and other stakeholders are realising that modern radiological protection requires a different approach.

At present, the ICRP is modernising its latest (2007) recommendations. Over 25 dedicated ICRP task groups have been undertaking a comprehensive revision of the entire system to address several issues to fill the gaps. However, the agency has yet to provide a target year: perhaps later this decade, not imminently. The International Atomic Energy Agency will also update its 2014 Basic Safety Standards using the ICRP’s inputs and publish it for universal acceptance.