Anfonwyd y mapiau at awdurdodau lleol ganol mis Rhagfyr 2009 ac fe’u gwnaed ar gael i ymatebwyr Categori 1 yn unol â Deddf Argyfyngau Sifil 2004.
The maps were issued to local authorities in mid December 2009 and also made available to Category 1 responders under the Civil Contingencies Act 2004.