Deviation Register
Template (Excel)

A deviation register is the project register of every formal deviation from the contract specification, the applicable code, the client standard, or the approved design basis. Each deviation row records the reference document, the discipline, the category (specification, code, client, vendor, site), the technical justification, the risk impact on safety and operability, the compensating measure, the approver, and the approval status. The register is the audit trail per ISO 9001 quality management practice that proves every accepted deviation was reviewed, risk-assessed, and approved by the authorised party before implementation.

At minimum: deviation ID, date, document or equipment reference, discipline, category, type (permanent, temporary, concession), the reference standard or spec clause, what the spec requires versus what is proposed, technical justification, risk category (low, medium, high), impact on safety and operability, compensating measures, reviewer, approver, approval status, approval date, conditions of approval, and closeout status. EPC contractors add a 'Linked NCR or MOC Reference' column so the register cross-references non-conformance reports and management-of-change records. The template includes the full standard column set.

Pathnovo, an engineering document intelligence platform, auto-tracks deviations by extracting deviation references from technical bid evaluations (TBE), vendor documents, inspection and test plans, and field non-conformance reports, then populating the register with category, discipline, and reference document. Open deviations are flagged against the Master Document Register and the affected equipment in the equipment list. Approval status is synced from the EDMS workflow. See the MDR automation workflow for the deviation-tracking pipeline.

A deviation is a pre-approved, planned departure from the spec or code, raised before the work is performed (for example, a vendor proposes a higher-grade material). A concession is a post-fact acceptance of a departure that was discovered after the work was complete (for example, a weld passed visual but failed a hardness check). A non-conformance report (NCR) is the formal record of any work that does not meet the spec, which may be rectified, accepted as a concession, or rejected. All three are tracked in the deviation register, distinguished by the Type column.

A deviation that changes the operating envelope, the safety case, the hazardous area classification, or the equipment integrity boundary must trigger management of change (MOC). The Linked NCR or MOC Reference column captures the MOC record ID. MOC adds the formal HAZID or HAZOP re-review for the proposed change before approval. Deviations that are purely editorial or below the MOC threshold do not require MOC. See the management of change standard reference and the HAZID standard reference.

Vendor deviations are raised in the vendor's bid, in the technical bid evaluation (TBE), in the vendor document submission cycle, or during fabrication. Each vendor deviation is logged with Originator = Vendor, the vendor's reference, and the EPC discipline lead as reviewer. Bid-stage deviations affect commercial alignment and must close before purchase order release. Fabrication-stage deviations are reviewed against the agreed datasheet and may require a concession. The register feeds the technical bid evaluation closeout per project procedure.

On brownfield and revamp scope, deviations often arise from the existing plant condition (for example, the as-built drawing shows different routing than the field, or existing equipment is at the end of life and exceeds the design code edition). Add a Scope column flagging deviations as 'existing-as-found', 'new-installation', or 'tie-in'. Existing-as-found deviations often require operator concession plus a fitness-for-service assessment per the relevant code (API 570 for piping, API 510 for vessels). The register feeds the brownfield management of change package.