IDAC meaning

An Interim Design Acceptance Confirmation (IDAC) is an interim statement from the Office for Nuclear Regulation (ONR) during the Generic Design Assessment (GDA) of a new nuclear reactor design. It records that ONR is broadly satisfied with the safety case and with the designer’s programme for resolving identified GDA issues, so the design may progress towards a full Design Acceptance Confirmation (DAC) once those issues are closed. In practice, an IDAC is issued to the reactor designer/requesting party and is relied on by prospective developers, investors and supply chains in UK nuclear new build. It helps de‑risk procurement, inform planning strategies and prepare for site-specific licensing. Legal status: the GDA, and the IDAC/DAC outputs, are non‑statutory and not defined in legislation or case law. An IDAC is not consent to construct or operate, does not grant a nuclear site licence and does not substitute for planning permission or environmental permitting. Jurisdiction: ONR’s GDA (and therefore IDAC/DAC) applies in Great Britain (England, Wales and Scotland). It is not used in Northern Ireland or Ireland. Environmental regulators may issue parallel (interim) statements on environmental matters during GDA, but these are distinct from the ONR’s IDAC. See also: DAC.