Sensor system design lacking at Buncefield
The final report on the Buncefield oil depot explosion in December 2005 says there is a need for considerable improvement in the design of sensing and control systems
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Buncefield Standards Task Group said in the report: “An examination of the records for Tank 912 from the ATG system suggest an anomaly in that the ATG system indicated that the level remained static while approximately 550m3/hr of unleaded petrol was being delivered into Tank 912.”
It added that overfill protection alarms or shutdown systems using high level switches or other two state detectors that were inactive for long periods may develop unrevealed faults.
“Overfill protection systems should be tested periodically to prove that they would operate safely when required,” it said. “Proof testing should be end to end, incorporating elements of redundancy and include the detector at the liquid interface and the valve closure element.”
The full report may be downloaded free of charge from www.hse.gov.uk/comah/buncefield/final.htm> The official government website on the disaster may be found at www.buncefieldinvestigation.gov.uk
