SFCS 2013 05 06 PiperAlpha 1 1 
National Aeronautics and Space Administration
NASA SAFETY CENTER
SYSTEM FAILURE CASE STUDY
M ay 2013 Volume 7 Issue 4
The Case for Safety
PROXIMATE CAUSE
• Simultaneous maintenance work on the pump and safety valve resulted in a condensate leak.
UNDERLYING ISSUES
• Defeated Design
• Negligent Culture
AFTERMATH
• The Cullen Inquiry resulted in 106 recommendations for changes to
North Sea safety procedures—all of which were accepted by the industry. • The Health and Safety Executive was to bear responsibility for
North Sea safety moving forward, replacing the Department of
Energy’s obligation, based on a conflict of interest for one organization to oversee both production and safety.
The North Sea Piper Alpha Disaster
July 6, 1988, Piper Oilfield, North Sea: As shifts changed and the night crew aboard Piper Alpha assumed duties for the evening, one of the platform’s two condensate pumps failed. The crew worked to resolve the issue before platform production was affected. But unknown to the night shift, the failure occurred only hours after a critical pressure safety valve had just been removed from the other condensate pump system and was temporarily replaced with a hand-tightened blind flange. As the night crew turned on the alternate condensate pump system, the blind flange failed under the high pressure, resulting in a chain reaction of explosions and failures across
Piper Alpha that killed 167 workers in the world’s deadliest offshore oil industry disaster.
Background
Piper Alpha
Constructed for oil collection by McDermott
Engineering and operated by Occidental
Group, Piper Alpha was located 120 miles northeast of Aberdeen, Scotland. It began exporting oil from the Piper Oilfield (discovered in 1973) to the Flotta Terminal on the Orkney
Isles in 1976. Modular in design, the four main operating areas of the platform were separated by firewalls designed to withstand oil fires, and arranged so that hazardous operating areas were located far from
NASA SAFETY CENTER
SYSTEM FAILURE CASE STUDY
M ay 2013 Volume 7 Issue 4
The Case for Safety
PROXIMATE CAUSE
• Simultaneous maintenance work on the pump and safety valve resulted in a condensate leak.
UNDERLYING ISSUES
• Defeated Design
• Negligent Culture
AFTERMATH
• The Cullen Inquiry resulted in 106 recommendations for changes to
North Sea safety procedures—all of which were accepted by the industry. • The Health and Safety Executive was to bear responsibility for
North Sea safety moving forward, replacing the Department of
Energy’s obligation, based on a conflict of interest for one organization to oversee both production and safety.
The North Sea Piper Alpha Disaster
July 6, 1988, Piper Oilfield, North Sea: As shifts changed and the night crew aboard Piper Alpha assumed duties for the evening, one of the platform’s two condensate pumps failed. The crew worked to resolve the issue before platform production was affected. But unknown to the night shift, the failure occurred only hours after a critical pressure safety valve had just been removed from the other condensate pump system and was temporarily replaced with a hand-tightened blind flange. As the night crew turned on the alternate condensate pump system, the blind flange failed under the high pressure, resulting in a chain reaction of explosions and failures across
Piper Alpha that killed 167 workers in the world’s deadliest offshore oil industry disaster.
Background
Piper Alpha
Constructed for oil collection by McDermott
Engineering and operated by Occidental
Group, Piper Alpha was located 120 miles northeast of Aberdeen, Scotland. It began exporting oil from the Piper Oilfield (discovered in 1973) to the Flotta Terminal on the Orkney
Isles in 1976. Modular in design, the four main operating areas of the platform were separated by firewalls designed to withstand oil fires, and arranged so that hazardous operating areas were located far from
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