Introduction: To design and implement a solution that creates a double vapour barrier system, to isolate steel riser and valve bridle pipework from the depressured buried pipe, and allow a guaranteed seal and monitoring to be achieved when completing hot work adjustments to the required pipework.

Objectives: To develop an adequate vapour barrier isolation solution that allows operatives to complete pipe asset repair and maintenance activities without the risk of explosive gases propagating into the working area (thus de-risk the operation) while keeping any residual product in the main pipeline.