SAFOP Methodology

Safety and Operability (SAFOP) Study is the application of a series of technical examinations and audits of high voltage generation, transmission and distribution of electrical systems to assess hazard potential to personnel and plan of mistaken operation of a system or malfunction of individual components and consequential effects including operator error.

A SAFOP is performed to provide a formal framework for a searching and systematic examination of engineering design in terms of effective operation and safety of personnel. A SAFOP study does not include detailed analysis of design calculations, design data (e.g., checking of protection settings, etc.) nor any initial review of a Manufacturer’s design capabilities (such as test certificates for items of plant, etc.).

A SAFOP shall form part of the project work scope for projects which do change the configuration of the High Voltage power generation and transmission system, or when new loads are connected to the system.

Objectives of a SAFOP Study are summarised as to:

Assess and minimise types of potential hazard presented to personnel in the vicinity of electrical installations.

Provide a critical review of both network design and plant to be installed and assess any limitations and their effects on both operability and security of the overall system.

Analyse tasks set for operators assess facilities and instructions provided to undertake these tasks and recommend measures to avoid operator error.

Three different studies are usually done under SAFOP, these are:

  • SAFAN – Safety Analysis
  • OPTAN – Operator Task Analysis
  • SYSOP – System Security & Operability of Plant Analysis

The brief methodologies of all three studies are given below:

SAFAN (Safety Analysis)

A SAFAN study may be divided into two distinct phases

  • An initial technical audit undertaken by the study team on conceptual design to examine an overall project in terms of safe operation and safety of personnel
  • A final SAFAN study carried out during the frozen design stage prior to manufacture, when construction drawings are available, giving detailed layouts of overhead lines and substations. These drawings can be examined now in detail by the study team to determine if project design permits safe operation with adequate safety of personnel.

Operator Task Analysis (OPTAN)

An OPTAN looks at probable tasks to be undertaken by both control room and field operators during normal and abnormal conditions. It assesses usability of equipment to be provided and reviews instructions necessary to prevent human error as far as is reasonably economic and practicable.

Anything which makes human operator’s work more difficult can lead to mistakes. Operators may develop poor work habits to cope with difficulties. This may lead them to either forget to do something, or to use wrong working methods. These habits may be tolerated under normal working conditions but are likely to give rise to serious problems when combined with power plant failure or loss of supply.

SYSOP – System Security & Operability of Plant Analysis

A SYSOP study may be undertaken in two distinct phases. They are:

  • An initial study should be conducted out on the conceptual design to help clarify the objectives of the project in terms of overall system security and operability.
  • A final study should be conducted at the ‘frozen’ design stage to study in detail the security and operability of a system, its plant and equipment.

This stage of study systematically questions engineering design and operation of a project to identify possible limitations and lack of flexibility, with their consequences to operability and security to a system.

Detailed examination of large, complex projects is facilitated by breaking-down projects into a number of discrete Elements for detailed examination. Elements should be small enough to be manageable and large enough to be of interest in terms of study objectives and, if possible, be a whole subsystem or unit of a complete system.

A system under study should be carefully examined to determine which parts to select as basic Elements.

These could be based on Isolation Points for major items of plant, or upon associated Protection or Operational Zones.

All three individual studies can be conducted independently of the other two, if necessary although it is recognised that there will be some necessary overlapping or cross-checking of individual studies. SAFAN and SYSOP studies certainly should be carried out, if possible, at both Initial and the Final phases of the project, but it is perhaps not so rewarding to carry out an OPTAN initial Study until the SYSOP Final Study is complete. Obviously, it is difficult to try and identify where operator error is possible when final design of the plant and ancillary equipment is not known. However, it may help in, selecting staff who will undertake Control Room and Field Operator duties.

SAFOP Methodology

Safety and Operability (SAFOP) Study is the application of a series of technical examinations and audits of high voltage generation, transmission and distribution of electrical systems to assess hazard potential to personnel and plan of mistaken operation of a system or malfunction of individual components and consequential effects including operator error.

A SAFOP is performed to provide a formal framework for a searching and systematic examination of engineering design in terms of effective operation and safety of personnel. A SAFOP study does not include detailed analysis of design calculations, design data (e.g., checking of protection settings, etc.) nor any initial review of a Manufacturer’s design capabilities (such as test certificates for items of plant, etc.).

A SAFOP shall form part of the project work scope for projects which do change the configuration of the High Voltage power generation and transmission system, or when new loads are connected to the system.

Objectives of a SAFOP Study are summarised as to:

Assess and minimise types of potential hazard presented to personnel in the vicinity of electrical installations.

Provide a critical review of both network design and plant to be installed and assess any limitations and their effects on both operability and security of the overall system.

Analyse tasks set for operators assess facilities and instructions provided to undertake these tasks and recommend measures to avoid operator error.

Three different studies are usually done under SAFOP, these are:

  • SAFAN – Safety Analysis
  • OPTAN – Operator Task Analysis
  • SYSOP – System Security & Operability of Plant Analysis

The brief methodologies of all three studies are given below:

SAFAN (Safety Analysis)

A SAFAN study may be divided into two distinct phases

  • An initial technical audit undertaken by the study team on conceptual design to examine an overall project in terms of safe operation and safety of personnel
  • A final SAFAN study carried out during the frozen design stage prior to manufacture, when construction drawings are available, giving detailed layouts of overhead lines and substations. These drawings can be examined now in detail by the study team to determine if project design permits safe operation with adequate safety of personnel.

Operator Task Analysis (OPTAN)

An OPTAN looks at probable tasks to be undertaken by both control room and field operators during normal and abnormal conditions. It assesses usability of equipment to be provided and reviews instructions necessary to prevent human error as far as is reasonably economic and practicable.

Anything which makes human operator’s work more difficult can lead to mistakes. Operators may develop poor work habits to cope with difficulties. This may lead them to either forget to do something, or to use wrong working methods. These habits may be tolerated under normal working conditions but are likely to give rise to serious problems when combined with power plant failure or loss of supply.

SYSOP – System Security & Operability of Plant Analysis

A SYSOP study may be undertaken in two distinct phases. They are:

  • An initial study should be conducted out on the conceptual design to help clarify the objectives of the project in terms of overall system security and operability.
  • A final study should be conducted at the ‘frozen’ design stage to study in detail the security and operability of a system, its plant and equipment.

This stage of study systematically questions engineering design and operation of a project to identify possible limitations and lack of flexibility, with their consequences to operability and security to a system.

Detailed examination of large, complex projects is facilitated by breaking-down projects into a number of discrete Elements for detailed examination. Elements should be small enough to be manageable and large enough to be of interest in terms of study objectives and, if possible, be a whole subsystem or unit of a complete system.

A system under study should be carefully examined to determine which parts to select as basic Elements.

These could be based on Isolation Points for major items of plant, or upon associated Protection or Operational Zones.

All three individual studies can be conducted independently of the other two, if necessary although it is recognised that there will be some necessary overlapping or cross-checking of individual studies. SAFAN and SYSOP studies certainly should be carried out, if possible, at both Initial and the Final phases of the project, but it is perhaps not so rewarding to carry out an OPTAN initial Study until the SYSOP Final Study is complete. Obviously, it is difficult to try and identify where operator error is possible when final design of the plant and ancillary equipment is not known. However, it may help in, selecting staff who will undertake Control Room and Field Operator duties.