PAS 128 Utility Survey (GPR & EML)
Technical Explanation
A PAS 128 survey is a standardized process (developed by BSI) for detecting and mapping underground utilities. It combines multiple methods: desktop records, site reconnaissance, geophysical scanning (using GPR and EML – electromagnetic locators for cables), and sometimes vacuum excavation to verify. The result is a utility map with quality levels indicating confidence.
Main requirements
Typically required before excavation or design in developed areas to avoid utility strikes. Needs access to utility records and a combination of GPR scanning and EML sweeps on-site. Adhering to PAS 128 ensures a consistent, reliable utility survey for construction planning.