Practical Application of the Best Protection Approach in Public Low-Dose Regulation: Operational Evaluation of Protection Effort Using the Protection Effort Index

This paper presents the operational and regulatory implementation of the Best Protection Approach (BPA) through the Protection Effort Index (PEI) for public protection during normal operation of nuclear power plants. The framework provides a practical alternative to dose‑centric approaches based on LNT and ALARA at very low doses, shifting the focus toward direct evaluation of the protection effort materialized in technological, operational, and quality‑assurance arrangements. It establishes a structural separation between verified technical information consolidated in the Safety Assessment Record (SAR) and the regulatory judgment expressed through PEI configurations. The paper describes the system‑level evaluation process, the controlled mapping from SAR information to PEI configurations, and the regulatory function of the lower and upper bounds of acceptability (C and J). The framework relies on competent regulatory judgment and supports clear, system‑based communication of public protection.