Method Process Safety

Testing and Commissioning

Some form of PSSR Pre-Start Up Safety Review or HS4 Hazard Study 4 should be carried out at the point of handover from the construction team to the testing and commissioning team. This is to ensure that the plant has been constructed according to the design intent, and that it is safe to proceed to testing and commissioning.

Testing and commissioning is the process of checking that everything installed on site was installed correctly and operates as intended. This stage typically involves on site loop testing of actuated valves, calibration of instrumentation, testing of pumps, and other operational tests. It is common practice to carry out water trials on equipment at this stage. This is a relatively non-hazardous method of checking the system operates as expected.

Upon completion of water trials, a hazard study 5 (HS5) is generally completed. This ensures that the system is ready and safe to start up with chemicals. HS5 confirms that:

  • All safety functions have been appropriately tested, with plans in place for appropriate maintenance
  • All commissioning tests were completed and operated as expected
  • All safety critical hazard study actions are complete
  • It is safe for the system to move on to full product trials

The commissioning team are responsible for carrying out the first product trials, before, before handing the plant over for normal operation. A review of commissioning should be carried out before the commissioning team disperse, to ensure that their knowledge is captured and acted upon. This is usually the first occasion when hazard study 6 (regular review) is carried out on a new process.

What =Method can do for you

  • Carry out independent verification of hazard studies carried out by others (a requirement of IEC 61511).
  • Provide experienced and independent PSSR / HS4 / HS5 facilitation.

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