Cause & Consequence
- Uncontrolled release of a flammable gas or liquid
Specific Incident Equipment
Bridle valve on dehydration pre-scrubber
- A needle valve was found to be open on the bridle vale which allowed a leak path to the open vent hole. The vale was believed to have been opened either due to being knocked or due to vibration on the equipment.
- There was no plug or instrumentation in place on the vent hole, leaving an open path to atmostphere for the condensate. The threaded vent port was rusted indicating there had not been a plug or instrumentation fitted to the valve for some time.
- Following investigation, it was determined that this was the only twin safe valve with this type of bleed arrangement. All other twin safe valves have flanged and blanked gate valve bleed assemblies.
- Systematic checks to be conducted on hydrocarbon systems in line with procedure 'Plant Integrity Verification Post Intrusive Maintenance' to confirm there are no similar issues.
- Proactive Hydrocarbon area hazard hunts implemented.
- Equipment added into vibration survey programme.