Disassemble instrumentation and control equipment and systems in engineering construction

Business Sectors (Suites): Maintaining Plant and Systems - Instrumentation and controls
Developed by: ECITB
Approved on: 28 Sept 2020


This standard is about disassembling instrumentation and control equipment and systems in engineering construction.

You will need to be able to disassemble instrumentation and controls systems and equipment.  You need to ensure that the system is safe prior to disassembly by discharging any residual or stored energy or substances and carry out isolations and disconnections using approved methods whilst adhering to health, safety and environmental legislation, regulations and safe working practices.
In the context of this standard, your responsibility is to interpret and work within given specifications, selecting methods and techniques to achieve the best possible result.  In some cases, you may still be expected to refer to others for final authorisation, even though you remain responsible for identifying and implementing decisions.

Who this standard is for
This standard is for instrumentation and control maintenance technicians.

Performance criteria

You must be able to:

  1. work safely at all times, complying with health, safety, environmental (HSE) and other relevant legislation, regulations, guidelines and local rules or procedures
  2. ensure that the work environment, materials, tools and equipment are suitably prepared for the work activities to be undertaken
  3. interpret and follow the relevant specification, as required
  4. establish what is being disassembled and match mark, if required, for reassembly
  5. make isolations and disconnections, and apply inhibits and overrides in line with local procedures
  6. ensure that any stored energy or substances are controlled and discharged  safely and correctly in accordance with HSE requirements
  7. ensure appropriate temporary support systems are in place for the task in hand
  8. carry out disassembly and, where appropriate, dismantling to the specified level using the correct tools and techniques
  9. take precautions to ensure the equipment, system and components are protected from potential ingress and potential damage from external influences and the environment
  10. if any components are removed then:

    • identify and record any that need replacing
    • dispose of any that are now redundant
    • correctly record, label and store those for reuse
  11. reinstate the work area

  12. deal promptly and effectively with problems within your control and report those that have been and those that cannot be solved

Knowledge and Understanding

You need to know and understand:

1. relevant legislative, regulatory and local requirements or procedures and safe working practices including your responsibilities with regards to reporting lines and procedures 2. preparation and reinstatement requirements in respect of the work area, materials, tools and equipment, and the possible consequences of incorrect actions in these areas 3. relevant engineering drawings and related specifications 4. how to ensure any stored energy or substances are controlled and discharged safely in accordance with HSE requirements 5. techniques for disassembly including: * how to ensure appropriate temporary support systems are put into place * instrumentation and control component and equipment removal and dismantling 6. the techniques for protecting against ingress protection and potential damage and the importance of this 7. how to check the condition of removed components and equipment and what to do if damage or defects are found 8. how to label and store instrumentation and control components and equipment for reuse 9. the correct disposal of waste, redundant and obsolete components and equipment 10. tool and equipment control:  the correct use of relevant tools and equipment and your individual responsibility for the use, care and security of those you use 11. reporting documentation and control procedures


Work environment

This could include:

  • engineering construction sites
  • controlled operations
  • offshore installations
  • maintenance sites
  • nuclear sites
  • repair sites

Work environments may be open or restricted spaces:  

  • at height 
  • confined spaces
  • control rooms
  • controlled operational and offshore installations
  • designated work areas
  • explosive atmospheres
  • existing plants and structures
  • fabrication workshops 
  • in plant rooms
  • inside structures, system and plant
  • on access structures (scaffold)
  • on open structures
  • onshore and offshore installations
  • shafts
  • shipyards
  • tunnels

Reinstate the work area
This term could include:

  • returning the work area to a safe condition
  • removing barriers
  • sweeping up
  • correctly disposing of waste materials
  • storing re-usable materials, consumables and equipment in accordance with appropriate procedures
  • completing  all necessary documentation

Scope Performance

Scope Knowledge





Disassemble: in the context of this NOS, disassemble means to take equipment or systems apart in a way which means that they can be reassembled.

Dismantle: in the context of this NOS, dismantle means to take equipment, systems or components apart and then label and store for reuse, recycle or dispose of the resulting parts.

Links To Other NOS

External Links

Version Number


Indicative Review Date

28 Sept 2020





Originating Organisation


Original URN


Relevant Occupations

Instrument and Control Maintenance Technician, Maintenance Engineer

SOC Code



instrumentation; control; electrical; engineering; potential ingress; soldering; dismantle; disassemble; engineering construction; plant; equipment; instrumentation and control systems