Positional Improvement
What is Positional Improvement (PI)?
Where old methods focused on the relative accuracy of the distance measured between two points on a map and the true distance between the same two points; new surveying methods capture the absolute accuracy distance between the position of a point on a large scale map and assess its true position within the reference frame using Global Positioning Systems (GPS).

- Downloadable version of the map (740KB)
If you are having difficulty viewing the map, please contact our PI section on 028 9038 8416
Latest PI Information
Update: 20 May 2013.
During the PI Project there will be minimal real world change captured. The above map shows those sheets that have been positionally improved. The diagram will be updated weekly.
All positionally improved sheets have corresponding link files available for customers.
