Coordinate Reference Systems
The DNF register of Coordinate Reference Systems is intended to give an overview of all the common spatial reference systems in use in the UK. The defining parameters for each will be published.
CRS Code  

OSGB 1936  View parameters 
ETRS89  View parameters 
TM75  View parameters 
OSNI 1952  View parameters 
IRENET 95  View parameters 
WGS84  View parameters 
British National Grid (OSGB 1936)
CS_NAME  OSGB 1936 / British National Grid 

SRID  27700 
AUTH_NAME  Ordnance Survey 
Coordinate System Type  Projected 
Datum  OSGB 1936 (EPSG ID 6277) 
Spheroid  Airy 1830 (EPSG ID 7001) 
SemiMajor Axis  6377563.396 
SemiMinor Axis  299.324964600 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
Projection  British National Grid (EPSG OP 19916) 
Latitude of Origin  49 
Central Meridian  2 
Scale Factor  0.9996012717 
False Easting  400000 
False Northing  100000 
E/N Units  Meter, 1 
Geocentric X Translation  446.44800 
Geocentric Y Translation  125.15700 
Geocentric Z Translation  542.06000 
Rotation XAxis  0.15020 
Rotation YAxis  0.24700 
Rotation ZAxis  0.84210 
Correction of Scale  0.9999795106 
European Terrestrial Reference System 1989 (ETRS89)
CS_NAME  ETRS89 

SRID  4258 
AUTH_NAME  EPSG. See 3D CRS for original information source. 
Coordinate System Type  Geographic 
Datum  European Terrestrial Reference System 1989 (EPSG ID 6258) 
Spheroid  GRS 1980 (EPSG ID 7019) 
SemiMajor Axis  6378137.000 
SemiMinor Axis  298.257222101 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
Irish Grid (TM75)
CS_NAME  TM75 / Irish Grid 

SRID  29903 
AUTH_NAME  Ordnance Survey of Ireland 
Coordinate System Type  Projected 
Datum  Geodetic Datum of 1965 (EPSG ID 6300) 
Spheroid  Airy Modified 1849 (EPSG ID 7002) 
SemiMajor Axis  6377340.189 
SemiMinor Axis  299.324964600 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
Projection  Irish Grid (EPSG OP 19972) 
Latitude of Origin  53.5 
Central Meridian  8 
Scale Factor  1.0000350000 
False Easting  200000 
False Northing  250000 
E/N Units  Meter, 1 
Geocentric X Translation  482.50000 
Geocentric Y Translation  130.60000 
Geocentric Z Translation  564.60000 
Rotation XAxis  1.04200 
Rotation YAxis  0.21400 
Rotation ZAxis  0.63100 
Correction of Scale  0.99999185 
Irish National Grid (OSNI 1952)
CS_NAME  OSNI 1952 / Irish National Grid 

SRID  29901 
AUTH_NAME  Ordnance Survey of Northern Ireland. 
Coordinate System Type  Projected 
Datum  OSNI 1952 (EPSG ID 6188) 
Spheroid  Airy 1830 (EPSG ID 7001) 
SemiMajor Axis  6377563.396 
SemiMinor Axis  299.324964600 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
Projection  Irish National Grid (EPSG OP 19973) 
Latitude of Origin  53.5 
Central Meridian  8 
Scale Factor  1.0000000000 
False Easting  200000 
False Northing  250000 
E/N Units  Meter, 1 
Geocentric X Translation  482.50000 
Geocentric Y Translation  130.60000 
Geocentric Z Translation  564.60000 
Rotation XAxis  1.04200 
Rotation YAxis  0.21400 
Rotation ZAxis  0.63100 
Correction of Scale  0.99999185 
Irish Transverse Mercator (IRENET 95)
CS_NAME  IRENET95 / Irish Transverse Mercator 

SRID  2157 
AUTH_NAME  Ordnance Survey of Ireland 
Coordinate System Type  Projected 
Datum  IRENET95 (EPSG ID 6173) 
Spheroid  GRS 1980 (EPSG ID 7019) 
SemiMajor Axis  6378137.000 
SemiMinor Axis  298.257222101 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
Projection  Irish Transverse Mercator (EPSG OP 19962) 
Latitude of Origin  53.5 
Central Meridian  8 
Scale Factor  0.9998200000 
False Easting  600000 
False Northing  750000 
E/N Units  Meter, 1 
Geocentric X Translation  
Geocentric Y Translation  
Geocentric Z Translation  
Rotation XAxis  
Rotation YAxis  
Rotation ZAxis  
Correction of Scale 
World Geodetic System 1984 (WGS84)
CS_NAME  WGS 84 

SRID  4326 
AUTH_NAME  EPSG. See 3D CRS for original information source. 
Coordinate System Type  Geographic 
Datum  World Geodetic System 1984 (EPSG ID 6326) 
Spheroid  WGS 84 (EPSG ID 7030) 
SemiMajor Axis  6378137.000 
SemiMinor Axis  298.257223563 
Prime Meridian  Greenwich 
PM Units  Decimal Degree, 0.01745329251994328 
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