English: Established Use Certificate
Welsh: tystysgrif defnydd sefydledig
Subject: Cynllunio
English definition: These were issued by a planning authority before July 1992 where it could be shown that a use of land or buildings had existed since before 1964. It gave immunity from enforcement action. Since July 1992 these have been replaced by Lawful Development Certificates.
Welsh definition: Cyhoeddwyd y rhain gan awdurdod cynllunio cyn Gorffennaf 1992 mewn achosion lle y gellid dangos bod defnydd o dir neu adeiladau wedi bodoli cyn 1964. Rhoddai imiwnedd rhag camau gorfodi. Ers Gorffennaf 1992 disodlwyd hwy gan Dystysgrifau Datblygiad Cyfreithlon.