From API RBI corrosion loops to Seveso III PSM— oil and gas compliance in 3 seconds.

API RP 581 (Risk-Based Inspection Methodology, 3rd edition) provides a quantitative framework for prioritising inspection resources in refining and petrochemical facilities. The methodology calculates a risk value by multiplying the probability of failure (PoF) by the consequence of failure (CoF) for each piece of equipment. Equipment is then grouped into “corrosion loops” — sections of piping and vessels experiencing the same corrosion mechanisms and rates. For each corrosion loop, the methodology assesses: the active damage mechanisms (e.g. high-temperature hydrogen attack, sulphidation, wet H2S cracking, hydrofluoric acid corrosion, naphthenic acid corrosion); the base corrosion rate and adjustment factors; and the PoF based on current thickness, expected remaining life, and inspection effectiveness. CoF is assessed in terms of financial consequences (property damage, business interruption) and area of potential impact for flammable/toxic releases. The result prioritises which equipment requires inspection soonest and what inspection technique (ultrasonic thickness measurement, radiography, AUT) is most appropriate. API RP 581 works alongside API 510 (pressure vessels), API 570 (piping), and API 653 (storage tanks) which specify the inspection intervals for each equipment type. IgeraIndustria has all four API RP standards indexed for corrosion engineers and inspection planners.

API 510 (Pressure Vessel Inspection Code, 10th edition) requires external inspections at a maximum interval of 5 years and internal/on-stream inspections at intervals not exceeding one-half of the remaining life or 10 years, whichever is less. For fixed-roof atmospheric storage tanks, API 653 (Tank Inspection, Repair, Alteration and Reconstruction, 5th edition) requires an out-of-service internal inspection every 10 years as a baseline, with risk-based adjustment using RBI (API 653 Appendix B) allowing extension to a maximum of 20 years. API 570 (Piping Inspection Code, 4th edition) classifies piping circuits into three risk categories: Class 1 (highest risk — flammable/toxic services above AIT or below boiling point) requires external inspection every 5 years and CML thickness measurement every 5 years; Class 2 (flammable services) every 10 years external and 10 years CML; Class 3 (low risk) every 10 years external and CML as determined by the inspector. All three codes allow extension of intervals through a risk-based inspection (RBI) programme that documents the assessment basis, the inspection techniques used, and the remaining life calculation. The RBI programme must be reviewed and revalidated when process conditions, operating temperature, or inspection findings change significantly. IgeraIndustria cross-references API 510/570/653 with your internal inspection planning documentation.

Seveso III (EU Directive 2012/18/EU) and the US OSHA Process Safety Management standard (29 CFR 1910.119) both govern major hazard prevention at facilities handling large quantities of dangerous substances, but they differ significantly in scope, thresholds, and approach. Seveso III is threshold-based: facilities are classified as “lower tier” or “upper tier” depending on the quantities of dangerous substances on site relative to Annex I thresholds. Upper tier sites must implement a Safety Management System, prepare a Safety Report (equivalent to the US PHA), have an External Emergency Plan coordinated with civil protection authorities, and participate in land use planning restrictions (Article 13). OSHA PSM 29 CFR 1910.119 applies to facilities with highly hazardous chemicals above threshold quantities (e.g. flammable liquids in a process with inventory above 10,000 lbs). PSM requires 14 elements including: Process Hazard Analysis (PHA, by HAZOP/What-If/Checklist), Mechanical Integrity programme, Management of Change (MOC), Pre-Startup Safety Review (PSSR), and an Emergency Action Plan. Key differences: (1) Seveso III has a land use planning dimension absent from PSM; (2) PSM requires a 3-yearly PHA revalidation; Seveso requires a Safety Report review every 5 years or after a major change; (3) Seveso triggers public information obligations under Article 14; (4) PSM has specific contractor safety requirements absent from Seveso. IgeraIndustria has both frameworks indexed for multinational oil and gas companies.

The BAT Conclusions for the Refining of Mineral Oil and Gas (EU Official Journal, August 2014, and the review launched in 2019) set BAT-Associated Emission Level (BAT-AEL) ranges that IED-permitted refineries must demonstrate compliance with. For sulphur dioxide (SO2): BAT-AEL for the overall refinery is expressed as a weighted average across all emission sources, with the refinery sulphur balance approach allowing total S in feed vs total S emissions to be benchmarked. Individual fired heater and boiler BAT-AELs are 100–600 mg/Nm³ (SO2) depending on fuel type and capacity. For NOx: combustion processes in refinery heaters BAT-AEL is 50–150 mg/Nm³ for gas-fired units and 50–200 mg/Nm³ for liquid fuel. For dust/particulate matter: BAT-AEL is 5–50 mg/Nm³ depending on the process unit. Fluid catalytic cracking (FCC) units have specific BAT Conclusions with tighter limits for CO (100–500 mg/Nm³), NOx (50–450 mg/Nm³) and SO2 (150–1,200 mg/Nm³ from the regenerator). IED permits must be updated to reflect current BAT Conclusions within 4 years of their publication. IgeraIndustria has the refinery BREF BAT Conclusions and associated emission levels indexed for environmental and process engineers.

Petroleum substances present a complex REACH SVHC challenge because many are registered as UVCB (Unknown or Variable composition, Complex reaction products or Biological materials) substances under REACH. The SVHC classification process for petroleum UVCBs has historically been contested due to difficulties in establishing composition-specific CMR properties. However, several petroleum-derived substances are on the ECHA SVHC Candidate List or Annex XIV: benzene (CAS 71-43-2) is on Annex XIV subject to authorisation, with sunset dates already passed for most uses; lead compounds used in certain refinery processes; and PAH-containing substances including coal tar-derived products. For SVHC Article 33 obligations in petroleum product articles: lubricants, process oils and other petroleum articles must be assessed for SVHC concentration above 0.1% w/w. The ECHA has published specific guidance on UVCB substances and how to assess SVHC presence. Authorisation applications for Annex XIV petroleum substances must be submitted to ECHA — the process typically takes 3–4 years from application to Commission decision, during which continued use requires a compliant application to be on file. IgeraIndustria tracks current Annex XIV sunset dates and authorisation status for petroleum substances.

Under the UK Mandatory TCFD Reporting regime (Financial Conduct Authority LR 9.8.6R and Companies Act Section 414CB), large UK-registered companies and UK-listed companies must provide TCFD-aligned disclosures in their Annual Reports. For UK refineries and oil majors, this means: Scope 1 direct GHG emissions from combustion in process heaters, flares, steam generation, FCC regenerators and fugitive methane emissions from equipment leaks — reported as CO2 equivalent using IPCC AR6 GWP100 values; Scope 2 indirect emissions from purchased electricity and heat; Scope 3 material upstream and downstream emissions, with Category 11 (use of sold products — combustion of refined fuels) being the most material for refineries, typically accounting for 85–90% of a refinery’s total GHG footprint. The TCFD Strategy pillar requires scenario analysis under at least a 1.5°C and a 2°C pathway, assessing physical risks (coastal flooding, water stress) and transition risks (carbon pricing, demand destruction for liquid fuels). The FCA Technical Note (March 2023) clarified that scenario analysis must be quantitative where feasible. The Climate Change Committee (CCC) expects UK refineries to align with the UK’s net zero pathway and disclose interim targets. IgeraIndustria maps TCFD requirements for refinery compliance and investor relations teams.