Pressure testing and commissioning of MEICA equipment is the highest-risk phase of any mechanical installation. Pipework, vessels, and process equipment are subjected to pressures exceeding normal operating levels to verify integrity. A failure during testing can release stored energy violently, propelling fittings and fluid at lethal velocity. Commissioning involves energising electrical systems and starting rotating equipment for the first time. Only trained and authorised personnel should carry out pressure testing and commissioning activities.
Key Hazards
Violent failure of pipework or fittings under test pressure causing fatal projectile injuries
Electric shock during first energisation of switchgear and motor control circuits
Rotating equipment starting unexpectedly during commissioning catching workers in moving parts
Produce a written test procedure for every pressure test specifying pressure, duration, and exclusion zones.
Establish physical exclusion zones around all pressurised equipment during the entire test period.
Restrain all end caps, blank flanges, and temporary fittings against the calculated thrust force.
Use only calibrated pressure gauges and test pumps with functioning relief valves.
Isolate and lock off all electrical supplies before carrying out any mechanical commissioning checks.
Verify all safety interlocks, emergency stops, and guard switches before first energisation of equipment.
Brief all commissioning personnel on the specific procedure, hazards, and emergency actions.
Clear the area of all non-essential personnel before starting any first-run test of rotating machinery.
Record all test results and commission each system in the sequence specified in the commissioning plan.
Emergency / Rescue
If a pressure test failure occurs, shut down the test pump and evacuate the exclusion zone immediately. For electrical incidents during commissioning, isolate the supply before approaching. Call 999 for any injuries.
Remember
Pressure testing failures can propel fittings with lethal force — exclusion zones are non-negotiable.
End caps and blank flanges must be mechanically restrained against the full thrust force during testing.
First energisation of electrical systems carries arc flash and shock risk requiring strict procedures.
Rotating equipment must have all guards and interlocks proven before the first operational run.
Only trained and authorised commissioning engineers should carry out these high-risk activities.
Record every test result because commissioning data forms the basis of the operational safety case.
Applicable Legislation: Pressure Systems Safety Regulations 2000 · Electricity at Work Regulations 1989 · PUWER 1998 · CDM Regulations 2015