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Procedure and Advice Guidance 121/25 Principal inspection interval risk assessment (PIIRA). Guidance note and user manual

Publication Year

2025

Document Status

Current

Abstract

Provides guidance on when and how to risk assess the frequency of inspections for bridges and other major road structures, using the Principal inspection interval risk assessment (PIIRA) process.

Document History

First published: 19 December 2025.

Publisher Information

Welsh Government

The Welsh Government is the devolved government for Wales. They publish a number of strategies, policies, consultation papers, circulars, leaflets and posters. Previously known as Welsh Assembly Government.