Define the line scope and operating boundary
Identify the line, process direction, start and end points, branches, operating states and adjacent equipment included in the work. Divide long or changing runs into traceable segments instead of relying on one description for the complete system.
- Mark tie-ins, branches and changes in elevation.
- Separate operating and shutdown conditions.
- Identify sections remaining in service or outside the work boundary.
- Assign a consistent segment code for photographs and inspection records.

