Radiation risk optimization and ALARA at the University of Utah.

摘要

The as-low-as-reasonably-achievable (ALARA) radiation protection standard as applied to a major research university is investigated. University administrators and radiation safety professionals must satisfactorily respond to the question "how safe is reasonable?" within the context of providing medical services, supporting sponsored research, and accommodating freedom of scientific inquiry in a changing regulatory environment. Subjected to similar competing regulatory and production cost conflicts, the nuclear industry has negotiated with regulators for quantitative cost-containment guidelines. These guidelines provide a benchmark threshold cost for collective radiation dose reduction. Cost-risk optimization, derived from risk-benefit theory, was used to support decisions that reduce unnecessary doses and assure cost-effective resource allocation.; On 1 January 1994, a revised Title 10, Code of Federal Regulations, Part 20, was promulgated by the U.S. Nuclear Regulatory Commission which requires compliance with the ALARA philosophy as a condition for receipt of a radioactive material license. The term "reasonably" in ALARA is now subject to firm regulatory interpretation. Satisfactory compliance with the rule requires facilities to evaluate, document, and quantify the uses, benefits, costs, and risks associated with radiation sources as well as demonstrate that beneficial social and economic factors justify their applications. Documented and quantified radiation risk assessment should now be applied to routine radiation operations to support their use.; Based upon historical operational data at the University of Utah, ionizing radiation usage and worker dose histories were summarized, and group risk prioritizations were performed. Radiopharmacy and nuclear medicine groups were identified as the highest priority users. The optimization program for activities that incur radiation-induced risk of fatal cancer in a lifetime has been developed to compare alternative protection strategies. Application of the quantitative risk optimization model to a research university shows that ALARA does not necessarily require costly upgrading of existing workstations but can usually be served through well developed and fully implemented administrative and operational radiological procedures.