Commissioning Field Lessons - Leave Out Lists

Written and experienced by me, not an algorithm

A ‘leave out list’ is information provided to a construction team (e.g. hydrotesting) to flag instruments and piping items required to be OUT for subsequent commissioning activities (flushes, blows etc). The items are then not reinstated by the construction team – if managed properly this helps both teams reducing man hours, materials and schedule.

I’ve seen this done well, and I’ve seen it done poorly, but what I’ve found key to successful execution

✅ early development of commissioning procedures

✅ proactive communication with construction engineering

✅ use of smart completions tools to automate the process

When this goes well and projects save money and time, it can often go unnoticed, but when it goes badly everyone can see the problem – commissioning teams taking apart systems that have literally just been reinstated by the hydrotesting crew.

On smaller piping systems its less of an issue, but when the leave outs require cranes, specialty gaskets or instrument hookup the inefficiency becomes significant.

At RFC Consultants, we can help prevent this by supporting project teams during early stages to develop strategies, procedures and best practices that can bring the construction and commissioning team together for an efficient, optimised execution in the field.