10.3 Coordinate reference systems

Each spatial dataset and geometry exchange shall identify its CRS by an authoritative name and identifier.

The CRS shall be defined in accordance with ISO 19111.

Where data is transformed:

source and target CRS shall be recorded;

transformation method and parameters shall be identified;

transformation date and software or service shall be recorded;

expected transformation accuracy shall be assessed; and

the transformed data shall be checked against known control or contextual information.

Data with an unknown or assumed CRS shall not be combined with controlled spatial information without a recorded assessment and approval.

JURISDICTIONAL NOTE (informative)
OSGB36 British National Grid is the national mapping CRS used by Ordnance Survey in Great Britain. Mapping and registration sources on the island of Ireland can use Irish Grid or Irish Transverse Mercator; current Tailte Eireann registration maps use ITM. The applicable CRS, transformation and vertical datum are to be stated in the project spatial data specification rather than inferred from the jurisdiction alone.