Industry Overlay — Petroleum / Oil and Gas

Petroleum and Oil and Gas Standards

Phase 11 — Corpus Complete

Industry Profile

Field Value
Industry Petroleum, oil and gas — onshore upstream / midstream / downstream
Typical systems ESD, F&G, HIPPS, wellhead control, pipeline control, compressor control
Markets US, international
Special concerns Hazardous areas (Ex), Safety Instrumented Systems (SIS), process safety management

Standards Applicability by Project Phase

Phase Standards Purpose
Concept / HAZOP IEC 61511 §5–6, ISO 12100 Hazard identification, consequence assessment
SIL Determination IEC 61511 §9 (LOPA), IEC 61508 Determine required SIL for each SIF
SIS Design IEC 61511 §10–11, IEC 61508 Part 2/3 Logic solver selection, SIF architecture, PFDavg calculation
Ex Equipment Selection IEC 60079-0, IEC 60079-10-1, IEC 60079-11 Zone classification, EPL/T-code selection, IS barrier sizing
Electrical Design IEC 60204-1, NEC Art. 500/504/505 Machine electrical, US hazardous location wiring
Installation IEC 60079-14, NEC Art. 300/250 Cable selection, IS segregation, equipotential bonding
Commissioning IEC 61511 §12, IEC 60079-14 §6 SIS FAT/SAT, Ex installation initial verification
Maintenance IEC 61511 §16 (proof testing), IEC 60079-17 Periodic SIF proof tests, Ex inspection regime

Standards Selection Flow

Is the installation in a hazardous area (flammable gas/vapor)?
  YES → Classify zones per IEC 60079-10-1
       → Select Ex equipment by EPL, gas group, T-code (IEC 60079-0)
       → US installation: NEC Art. 505 (Zone) or Art. 500 (Division)
       → IS field devices: IEC 60079-11 + entity parameter check

Does the process have a credible loss-of-containment hazard?
  YES → Perform HAZOP (IEC 61511 §5)
       → Determine if a Safety Instrumented Function (SIF) is required
       → Run LOPA to establish SIL target
       → Design SIF per IEC 61511 §10

Is the SIL target ≥ SIL 3, or is the logic solver a custom design?
  YES → Apply IEC 61508 directly for logic solver development
  NO  → IEC 61511 reference to IEC 61508 is sufficient

Standards Path Summary

Category Standards Corpus Status
US electrical installation NEC Art. 240, 250, 300, 500, 504, 505 Complete
Machine electrical design IEC 60204-1 Complete
Process safety (SIS) IEC 61511 Complete
SIS foundation IEC 61508 Complete
Hazardous area equipment IEC 60079 (6 parts) Complete
API standards API 14C, API 670 Not in corpus

Key Engineering Decisions for O&G

Zone vs. Division classification: IEC Zone (Art. 505) is preferred when using ATEX/IECEx certified equipment. NEC Division (Art. 500) is used on legacy US installations. Both are legally valid in the US — verify with AHJ.

Zener barrier vs. galvanic isolator: Use zener barriers where a dedicated IS earth ≤1 Ω is available and galvanic isolation is not needed. Use galvanic isolators where multiple ground loops cause measurement errors or where the field device is floating. See IEC 60079-11.

SIL 2 vs. SIL 3 architecture: SIL 2 SIFs can typically be achieved with 1oo2 or 2oo3 voted architectures using proven-in-use devices. SIL 3 generally requires 1oo2D or 2oo3 with hardware fault tolerance ≥2 and full IEC 61508 application for the logic solver.

Pre-Commissioning Compliance Checklist

See Oil & Gas Process Skid scenario →

← Industry matrix

Trust Boundary — Engineering Judgment Required

This site is a personal-use paraphrase and navigation reference for industrial automation standards. It is not a substitute for authoritative standards documents, professional engineering judgment, or legal review. All content is sourced from a local RAG corpus and has not been independently verified against current published editions.

Items marked TO VERIFY have limited or unconfirmed local coverage. Items marked NOT IN CORPUS are not covered in the local repository. Do not rely on this site for compliance determinations, safety-critical design decisions, or legal interpretation.