1. Scope and structure
| Term | Meaning |
|---|---|
| Tag | A unique identifier for a physical item — valve, instrument, motor, vessel, cable. The atom of completions data. |
| System | A complete functional group, such as instrument air or seawater cooling. |
| Subsystem | An independently testable division of a system. The unit that gets certified and handed over. See systems and subsystems. |
| Master data | The controlled register of tags, systems and subsystems that every other record references. |
| Boundary | The physical limit of a subsystem, marked on the P&ID, where it can be isolated from its neighbours. |
2. Records and evidence
| Term | Meaning |
|---|---|
| ITR | Inspection and test record. Signed proof a defined check was performed on a tag. See the ITR guide. |
| A-ITR | Static inspection record completed before energisation. Feeds mechanical completion. |
| B-ITR | Dynamic record completed after energisation — loop checks, function tests. Feeds RFSU. |
| Checksheet | The blank template; the ITR is its completed, signed instance against a tag. |
| CP | Commissioning procedure — a controlled step-by-step document governing how a system is brought into service. |
| PWL | Preservation work list. The register of recurring preservation routines. See the preservation guide. |
| Walkdown | A structured physical inspection of a subsystem against documentation. See the walkdown guide. |
Put a number on it
What is this costing your project right now?
Estimate the hours and cost lost to transcription, register consolidation and dossier assembly — with editable assumptions and the maths shown.
3. Punch and deficiencies
| Term | Meaning |
|---|---|
| Punch item | A recorded deficiency found during inspection, walkdown or testing. Also called a snag. |
| Category A | Blocks the next milestone — safety, function or ability to proceed. |
| Category B | Does not block progression but must be closed before final handover. |
| Category C | Cosmetic or minor; closed on a best-efforts basis. |
| Close-out | Correction of an item plus evidence and an authorised acceptance signature. |
4. Milestones and phases
| Term | Meaning |
|---|---|
| MC | Mechanical completion. The subsystem is built to design and statically inspected. |
| Pre-commissioning | Preparation after MC and before energisation — flushing, cleaning, calibration, loop checks. |
| Commissioning | Energised function testing under controlled procedures. |
| RFSU | Ready for start-up. Safe to place in service; custody normally transfers here. |
| Care, custody and control | The formal responsibility for a subsystem's condition and safe operation, which transfers at a defined milestone. |
| Final acceptance | Post start-up and performance testing, once the dossier is issued and punch is closed. See handover and RFSU. |
5. Field and testing terms
| Term | Meaning |
|---|---|
| Loop check | Verification that a control loop functions end to end, from field instrument through to the control system. |
| Solo run | Running a motor uncoupled to verify rotation, vibration and temperature before it drives anything. |
| FAT / SAT | Factory and site acceptance testing — vendor testing before shipment and equivalent verification once installed. |
| Energisation | First application of power or process medium to a subsystem, after which the safety regime changes. |
| As-built | Documentation updated to reflect what was actually installed rather than what was designed. |
Check your own process
Score your handover readiness in eight questions
A structured self-assessment of register control, evidence capture, sign-off and gate logic — with a specific recommendation for every gap.
