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Process Safety Engineering

HAZOP, LOPA, SIL/SIS, Dust Hazard Analysis and consequence modelling — technically rigorous process safety studies delivered across Africa.

Process Safety Engineering

Identifying Hazards Before They Become Incidents

Process safety engineering is the technical cornerstone of any high-hazard operation. Nexis Process Safety delivers structured, independently facilitated studies that systematically identify hazards, quantify risk and recommend proportionate safeguards — giving your engineering and management teams the evidence base to make confident safety decisions.

Our studies conform to IEC 61882 (HAZOP), IEC 61511 (SIL/SIS), IEC 60079, NFPA 652/654 (DHA), PSSR 2000, and the CCPS Guidelines for Chemical Process Quantitative Risk Analysis. Every deliverable is audit-ready, regulator-defensible and practically implementable.

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Core Studies Delivered

  • HAZOP (Hazard & Operability Studies) — IEC 61882
  • LOPA (Layer of Protection Analysis)
  • SIL / SIS Assessment — IEC 61511 / IEC 61508
  • Dust & Combustible Dust Hazard Analysis (NFPA 652/654)
  • Electrostatic Hazard Studies
  • Machine Safety — PSSR 2000 / Machinery Directive
  • Process Consequence Modelling
  • Reactive Chemical Hazard Studies
  • What-If / Checklist Analysis
  • Failure Modes and Effects Analysis (FMEA)
HAZOP Studies

Systematic Identification of Process Hazards

A Hazard and Operability Study (HAZOP) is the industry-standard technique for systematically examining a process design to identify potential hazards and operability problems. Nexis PS facilitates structured HAZOP reviews that go beyond regulatory box-ticking.

What We Examine

  • Piping and Instrumentation Diagrams (P&IDs)
  • Operating procedures and control philosophy
  • Utility systems and support services
  • Startup, shutdown and emergency modes
  • Human factors and task criticality

What You Receive

  • Full HAZOP worksheets (HAZOP software or Excel)
  • Action register with recommended safeguards
  • Risk ranking against agreed risk matrix
  • Close-out tracking log
  • Presentation-ready executive summary

Industries Served

  • Oil & gas (upstream and downstream)
  • Chemical and petrochemical manufacturing
  • Food & beverage (flammable / toxic materials)
  • Mining (processing and reagent handling)
  • Pharmaceutical and specialty chemicals
LOPA & SIL Assessment

Quantifying Risk and Validating Safety Instrumented Systems

Layer of Protection Analysis (LOPA) and Safety Integrity Level (SIL) studies are required wherever Safety Instrumented Functions (SIFs) are used to reduce process risk to tolerable levels.

LOPA

A semi-quantitative technique that evaluates Independent Protection Layers (IPLs) against initiating event frequencies to determine whether risk is tolerable or whether a Safety Instrumented Function is required.

  • Initiating event frequency determination
  • IPL credit assignment and documentation
  • Consequence severity classification
  • Risk gap identification and SIF target SIL

SIL Assessment — IEC 61511

We determine the required SIL for each Safety Instrumented Function and verify the SIS design is capable of meeting that SIL, in accordance with IEC 61511 (SIS for the process industry).

  • SIL target determination (LOPA / risk graph / risk matrix)
  • SIL verification (PFDavg calculation)
  • Architectural constraints review (IEC 61511 Clause 11)
  • Safe Failure Fraction (SFF) assessment
  • Proof test interval optimisation
Dust Hazard Analysis

Understanding and Managing Combustible Dust Risks

Combustible dust explosions remain one of the most underestimated process safety hazards globally. Nexis PS conducts thorough Dust Hazard Analyses (DHA) aligned to NFPA 652 and NFPA 654 to identify, assess and control these risks.

Scope of a DHA

  • Dust combustibility / explosibility screening
  • Identification of dust hazard areas and ignition sources
  • Assessment of existing dust control and explosion protection measures
  • House-keeping programme evaluation
  • Emergency response and explosion venting review

Applicable Standards

  • NFPA 652 — Fundamentals of Combustible Dust
  • NFPA 654 — Prevention of Fire and Dust Explosions from Manufacturing, Processing, and Handling of Combustible Particulate Solids
  • ATEX Directive 1999/92/EC (European export clients)
  • IEC 60079-10-2 Zone classification (combustible dust)
  • SANS 10108 (South African equivalent)
Why Nexis PS

Technical Excellence. Practical Outcomes.

Regulator-Defensible

Every study is documented to withstand regulator scrutiny and third-party audit — HAZOP worksheets, LOPA workbooks, SIL verification calculations.

Independent Facilitation

We facilitate studies independently, free from equipment vendor or project contractor influence, ensuring genuine risk identification rather than rubber-stamping.

Knowledge Transfer

We brief your team throughout the study and provide training on safeguard ownership and action close-out so the value is sustained long after we leave.

Africa-Context Delivery

We understand the operational realities of African industry — variable utility supply, staffing constraints, import lead-times — and factor these into every recommendation.

Ready to Work With Nexis PS?

Talk to our process safety specialists today. We'll tailor a solution to your hazard profile, regulatory context, and operational goals.

Process Safety Specialists
SANS / IEC / ISO Expertise
Africa-Wide Coverage
24h Response Guarantee