Changes to Control Mark Orders

The Orders of control marks have been updated to reflect the accuracy definitions in the LINZS25005 and LINZS25006 standards.

These standards did not change the way that the control Orders are numbered.

The major change to the control mark Orders was the simplification of the network accuracy tolerances. Network accuracy was previously known as ‘absolute accuracy’ and the maximum errors were defined to the millimetre level. LINZS25006 has grouped these values into 5cm bands (called Tiers) that are more meaningful to users. This means that the same Tier can be defined for several Orders. Minor changes were also made to the local accuracy values for Orders 0 and 5.

The new control mark Orders and the changes from the previous system are summarised in the following table:

Order Purpose Network Accuracy Local Accuracy
Tier Absolute (old) Horizontal Vertical
Horiz
(m)
Vert
(m)
Horiz
(m)
Vert
(m)
  Constant
(m)
Proportion
(m/m)
  Constant
(m)
Proportion
(m/m)
0 National Reference Frame A 0.05 A 0.05 0.050 0.150 II 0.003 3x10-8
(1x10-8)
II 0.003 3x10-8
1 National Deformation Monitoring A 0.05 B 0.10 0.071 0.201 III 0.003 1x10-7 IV 0.003 3x10-7
2 Regional Deformation Monitoring B 0.10 E 0.30 0.087 0.260 V 0.003 1x10-6 VI 0.010 3x10-6
3 - B 0.10 E 0.30 0.100 0.300 VI 0.010 3x10-6 VII 0.010 1x10-5
4 Local Deformation Monitoring C 0.15 F 0.35 0.112 0.335 VII 0.010 1x10-5 VIII 0.010 3x10-5
5 Cadastral Horizontal Control; Geospatial C 0.15 F 0.35 0.122 0.367 VIII 0.010 5x10-5
(3x10-5)
IX 0.020
(0.010)
1x10-4

Previous values are shown in italics. Vertical errors relate to ellipsoidal heights determined with the horizontal coordinate. There is a separate set of height Orders for normal-orthometric heights. Find out about changes to cadastral mark Orders.