4.9 HRBs are defined in the Building Act 1984 and described in the Building Safety (Description of Higher-Risk Building) (Design and Construction Phase) (Wales) Regulations 2023.
4.9 Mae adeiladau risg uwch wedi’u diffinio yn Neddf Adeiladu 1984 ac wedi’u disgrifio yn Rheoliadau Diogelwch Adeiladau (Disgrifiad o Adeilad Risg Uwch) (Cyfnod Dylunio ac Adeiladu) (Cymru) 2023.