RBI Worksheet — API 581

A simplified Risk-Based Inspection workbook aligned with API 580 / 581. Capture asset register, damage mechanism scoring, POF and COF, the 5x5 risk matrix, and the inspection mitigation plan.

Risk-Based Inspection (RBI) is the methodology defined in API 580 (concepts) and API 581 (quantitative) for prioritizing inspection effort by the risk that asset failure would expose to safety, environment, and finance. RBI is now the default in-service inspection model for refineries, petrochemical plants, and offshore facilities.

Use this worksheet to capture the inputs and outputs of a qualitative or semi-quantitative RBI study. Populate the Asset Register, score each applicable damage mechanism, derive POF and COF, place each asset on the 5x5 matrix, and generate the inspection plan. The template is intentionally lean — extend with the full API 581 Part 2 calculation if quantitative results are needed.

Atlantis NDT can build a full quantitative RBI study and integrate the results into a live integrity-management dashboard.

Atlantis NDT runs API 581 quantitative studies and integrates the results into integrity-management dashboards.

What this page covers

Overview
Sheets Included
Related Free Templates
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Key points covered

Asset register — 15 assets with tag, description, equipment type, design code, last / next inspection
Damage mechanisms — 20 mechanisms (general / localized / pitting / SCC / HIC / CUI / creep / fatigue) per asset
POF / COF / Risk — generic failure frequency, damage factor, POF cat 1-5, COF safety / environmental / financial, composite COF
Risk matrix — full 5x5 matrix (Low / Medium / High / Very High) per API 581
Inspection plan — recommended NDT, target effectiveness, coverage %, due date
Sign-off — RBI facilitator, inspection engineer, process / corrosion engineer, operations, asset owner

Using the RBI worksheet honestly

A risk-based inspection worksheet is a structured argument, not a scoring exercise: probability of failure built from damage mechanisms and measured corrosion data, consequence from inventory and location, combined into a risk ranking that justifies each interval. The worksheet fails silently when its inputs go stale — default corrosion rates where measured ones exist, damage mechanisms unrevisited after a feedstock change, consequence categories copied between dissimilar items. Record the basis beside every entry; an RBI decision whose basis cannot be produced is, to an auditor, a guess with formatting.

The worksheet's most valuable column is the one teams skip: what inspection finding would change this ranking. Writing it forces the interval to be falsifiable — and tells the next campaign exactly what to look for. API 580 sets the framework; API 581 the quantitative method; this worksheet is where both meet your actual equipment list.

Where this document sits in the wider system

Templates fail as loose files and work as parts of a system: this document should cross-reference the records that feed it and the decisions it feeds, carry a revision history like any controlled document, and live where the whole team retrieves the CURRENT version — not the copy someone improved privately last year. Companies running their inspection operations on a single system of record generate most of these documents from live data rather than filling them by hand; that is the practical difference between managed records and managed paperwork. Browse all templates and resources, or ask how the generated version works.