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Oil & Gas Industry Training

ESD, SIS and SIL determination methods


Increasingly, industrial processes within the petrochemical, chemical and nuclear power industries have the potential for large-scale destruction. Without the luxury of learning from experience, organisations must anticipate and set in place preventative measures before accidents occur.

This workshop, ‘ESD, SIS and SIL determination methods’, is designed to provide instrumentation and control system engineers and technicians with the basic theoretical and practical tools that will enable them to evaluate, design, install and maintain safety instrumented systems according to ISA S84 and IEC 6150811. It will also acquaint instrumentation and control system engineers with the essentials of the safety system and it relates to the safety life cycle of the plant.

Delegates will also examine the pros and cons of both quantitative and qualitative methods of SIL determination with particular emphasis on Layers of Protection Analysis (LOPA). Other issues include:

  • hazard and risk reduction
  • technology choices
  • reliability analysis
  • selection of field devices
  • hardware and software engineering
  • validation
  • operations and maintenance

What you will learn

The course is based on a wealth of experiential knowledge gleaned from the author's experience working within a systems integration company and also feedback from more than 4000 technicians and engineers who have attended the author’s workshops. On successful completion of this workshop delegates will be able to:

  • appreciate the background to IEC 61598 and the ISA S84 standards and understand their differences
  • understand the concept of the Fatal Accident Rate (FAR)
  • apply the Safety Lifecycle model
  • determine the SIL level using quantitative and qualitative methods including Layers of Protection Analysis
  • outline the methodologies used in HAZOPs
  • identify hazards and understand the specifications of the protection requirements
  • distinguish between overt and covert failures
  • select and specify different technologies and learn how to apply them
  • understand the concepts of Safe Failure Fraction, Coverage Fraction and Common Cause Failures
  • apply reliability formulae and their correct allocation
  • examine and evaluate redundancy choices
  • apply reliability data to a specific application
  • recognise the impact of test intervals
  • appreciate the requirement for sensor and valve diagnostics
  • perform instrument selection
  • appreciate the role of Safety critical transmitters and positioners
  • recognise the responsibilities of the operating company, the engineering company and the vendor
  • engineer a protection system
  • follow the basic steps required during installation and commissioning
  • adhere to the steps required for operations, maintenance and control of changes

Training methodology

Delegates will examine:

  • hazard and risk reduction
  • technology choices
  • reliability analysis
  • selection of field devices
  • hardware and software engineering
  • validation
  • operations and maintenance

Throughout the workshop, participants will learn through active participation using exercises, questionnaires, and reliability calculation software.

Who should attend

Personnel who are or will be responsible for the designing, selecting, sizing, specifying, installing, testing, operating and maintaining instrumentation safety systems

  • Asset management team members
  • Automation Engineers
  • Consulting Engineers
  • Design Engineers
  • Electrical Engineers
  • Electricians
  • Installation and Maintenance Technicians
  • Instrument Fitters
  • Maintenance engineers
  • Maintenance team leaders
  • Mechanical engineers and technicians
  • Operations Engineers
  • Operations team leaders
  • Process Engineers
  • Process Operators
  • Production Managers
  • Project Managers
  • System Integrators
  • Team leaders/coordinators
  • Instrument and Process Control Engineers and Technicians


Workshop length

5 days

What you will receive

  • ‘ESD, SIS and SIL determination methods’ – a 300-page reference manual.
  • Acrobat copy of all PowerPoint slides used in the presentation on USB Flash Memory Drive.
  • Certification of attendance: each delegate will receive a workshop certificate documenting their attendance

What people say:

“Mick has received excellent reviews and positive feedback for all his courses. His down-to-earth, practical, and entertaining approach makes him a sought-after speaker and lecturer in a wide variety of disciplines.” - IDC Technologies
“Presented in an easily understood manner.” - E. Maughn, Eskom
“Really knows his subject.” M. Radcliff, Houston Texas
“Gained useful insight into a complex subject” - E. Carter, Johannesburg, South Africa


Introduction to safety instrumentation

  • Hazards and risks
  • Fatal Accident Rate (FAR)
  • Safety systems engineering
  • Introduction to standards
  • IEC 61508 and ISA S84
  • Definitions
  • The Safety Lifecycle model

Hazard and risk reduction

  • Hazards
  • Process control vs. safety control
  • Protection layers
  • Risk reduction in classification
  • Safety Integrity Level (SIL)

Hazard studies

  • Outline of methodologies
  • Hazard study 1
  • Hazard study 2
  • Hazard study 3
  • Risk analysis and reduction
  • Evaluating SIS requirements
  • Adding protection layers

Technology choices

  • Pneumatics
  • Relays
  • Solid-state systems
  • Programmable systems
  • Upgrading standard PLCs
  • Safety PLCs
  • Triple modular redundant systems
  • System architectures

Reliability analysis

  • Failure modes
  • Overt vs. covert failures
  • Diagnostic modes
  • Reliability formulae
  • Allocation of formula
  • Calculation example
  • Steps in SIS analysis
  • Reducing manual proof testing

Selection of field devices

  • Failure modes
  • Design requirements
  • Diversity
  • Proven in use
  • Sensor diagnostics
  • Valve diagnostics
  • Instrument selection
  • Safety critical transmitters and positioners

Hardware engineering

  • Role of operating company
  • Role of engineering company
  • Role of vendor
  • IEC and ISA recommendations

Software engineering

  • Software life cycle
  • Application software
  • Limited variability languages
  • Software on the management
  • Certification

Overall planning

  • Maintenance and operations planning
  • Validation planning
  • Installation and commissioning planning

Installation and commissioning

  • Factory acceptance tests
  • Installation and
  • Handover

Safety validation

  • Verification
  • Validation
  • Functional safety assessment

Operations and maintenance

  • Maintenance program
  • Functional testing

Management of change

  • Deployment
  • Procedural model
  • Impact analysis
  • Software changes

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