PAS 128 provides a robust methodology for delivering utility surveys in the UK. It focuses on levels of accuracy – referred to as Survey Category Types – that you can specify when requiring a PAS 128 compliant underground utility survey.
The four different survey types which can be used to determine the quality level of survey data provided to the client by the surveyor:
- PAS 128 Survey Category Type D
Desktop Utility Record Search. A thorough desktop search of all statutory asset owners to supply their record data. Sometimes referred to as a C2 Search.
- PAS 128 Survey Category Type C
Underground utility plotted from utility record data only, but with site reconnaissance to match utility record with physical utility street furniture as a best fit.
- PAS 128 Survey Category Type B
An on-site utility mapping survey using multiple geophysical instruments. The output from this survey shall be each linear 5 metre section of utility depicted as a Quality Level (QL) 1-4 for horizontal and vertical detection accuracy.
- PAS 128 Survey Category Type A
Utility verified and positioned by physical identification. This may be by strategically positioned vacuum excavation, hand dug trail pitting or by visual inspection within a utility chamber.
PAS 128 is a useful tool for our clients as it helps to determine the type of survey that they need, and the methodology required. Utilising these guidelines, we can establish which survey grid to use; whether or not to employ post-processing of GPR data; and specific scenarios where survey levels are defined.
We were proud industry leaders in implementing PAS 128 since its inception and we integrate the full scope of the guidelines into our internal training so that all of our surveyors are fully compliant with the practice, and able to offer a comprehensive service to all of our requirements.
Survey quality is paramount, and we ensure this by utilising multiple detection methods and verifying the 3D dimensions as accurately as possible. The different detection methods, from M1 through to M4 are influenced by the density and risks associated with the area, and as required we have a team of technicians who are expert in GPR data postprocessing and are able to work on the GPR data away from site to maximise the information obtained from the data.
If you require a Utility Survey Send us an enquiry.