The horror of the Piper Alpha disaster happened about two decades ago. Explosion and fire ripped through the Piper Alpha oil production platform in the North Sea off the coast of Scotland. About 167 workers were killed as a result of the Piper Alpha Disaster.
Several investigations were made but most of them were hindered by a lack of physical evidence. However, an eye-witness account made it known that light hydrocarbon got released into the surrounding when a pump was restarted after maintenance. On that terrible day, the day shift maintenance crew were said to be on some of the pumps used for gas compression. One pump was taken out for routine maintenance, the pipe was then temporarily sealed using a flat metal disk. The work could not be completed during the day shift change-over, as a result, the metal disc was left as the day shift left and the night shift resumed duty not aware of the position of the pipe and pump. Later in the day, the pump under maintenance was switched on after the other condensate pump stopped working; upon this restart, the flange leaked, this led to the leakage of gas at high pressure creating a cloud of hydrocarbon which got ignited when it met with an ignition source and thereby exploding. Since the Piper Alpha platform was at the pivot of a system of platforms which are interlocked with oil and gas pipelines. The first explosion led to the explosion and rupture of the oil lines on Piper Alpha, with the leaks still being fed into the pressurized pipelines. Communication was interrupted, which made the managers on other platforms unaware of how severe the problem at the Piper Alpha is. It took about 30 to 60 minutes before other platforms got shut in. And when they did, many of the platform crew retreated to the platform crew awaiting evacuation but unfortunately no organized attempt was made to evacuate the accommodation module. This resulted in the death of the workers.
It was learnt that about a year before the explosion, an engineering report was received by the company management and had been cautioned that, if a large fire should occur from escaping gases, it would pose as regards the safe evacuation of the platform. It is a shame that the management disputed the likelihood of such event occurring, believing so much in the already installed protection systems. They forgot to take into account that the emergency isolation valves on Piper Alpha were not fire proofed and therefore susceptible to fire, also, it will take several days to depressurize these pipelines due to their diameter and length. The failure of these pipelines was what led, majorly, to the destruction of the Piper Alpha and prevented the evacuation of its platforms.
One of the major lessons that should be learnt from the Piper Alpha disaster is that the quality of safety management is crucial and the standard for safe systems of work must be duly adhered, including permit-to-work system. Also, there need to be a provision for the adequate and effective communication between all workers affected by any maintenance routine. The maintenance plant should be located at an isolated area. All workers and managers needs to undergo safety training. Also, the Post Piper Alpha studies made it known that there is a critical need for corrosion management and that it is important to include the pressure vessel and the piping community in this.
Answer to Question 1
Several human errors contributed to the severity of the disaster with the major one being the lack of effective communication in shift handovers. The lack of information accuracy and the incompleteness from the day shift workers to the night shift workers is the reason behind the disaster.
It was learned that, about a year before the explosion, an engineering report was received by the company management. The report contained a caution stating that, if a large fire should occur from escaping gases, it would pose as regards the safe evacuation of the platform. It is a shame that the management disputed the likelihood of such event occurring, believing so much in the already installed protection systems. The management forgot to take into account that the emergency isolation valves on Piper Alpha were not fire proofed and therefore susceptible to fire, also, it will take several days to depressurize these pipelines due to their diameter and length. The failure of these pipelines was what led, majorly, to the destruction of the Piper Alpha and prevented the evacuation of its platforms.
Answer to question 2
Yes, the Swiss-Cheese model can be applied to the Piper Alpha disaster. This is because the Swiss-Cheese model of accident causation is a model which has been created to analyze risks and manage them. Most of the reasons behind the Piper Alpha disaster are related to how risks were analyzed and managed by everyone involved. The Swiss cheese model is such a theoretic framework which has been based on a very solid behavioral theory; it therefore can be used to provide roadmap for the analysis of this Piper Alpha disaster since with it a generic safety assessment framework can be modeled. Also, the model describes how generic organizational and human errors can be disintegrated into logical and mutually exclusive categories with each one influencing the other that’s next to it. Also, the Swiss Cheese Model can be employed to create a five-level framework which may be proposed to address covert failures within the causal sequence of events that led to the disaster. This five-level frame work will include Incidents level, Trigger events level, Accidents level, Root causes level, and Consequences level.
Answer to question 3
One of the major lessons that should be learnt from the Piper Alpha disaster is that the quality of safety management is crucial and the standard for safe systems of work must be duly adhered, including permit-to-work system. Also, there need to be a provision for the adequate and effective communication between all workers affected by any maintenance routine. The maintenance plant should be located at an isolated area. All workers and managers needs to undergo safety training. Also, the Post Piper Alpha studies made it known that there is a critical need for corrosion management and that it is important to include the pressure vessel and the piping community in this.
The firewalls should have been upgraded or replaced with blast walls, this would have withstood the initial fire and prevent it from getting to other modules.
Emergency shutdown valves should have been placed on the deck within a blast-proof container.
Offshore should be designed in such a way that it would limit the supply of hydrocarbons to the installations.
There should be a temporary shelter that has been created to be smoke, fire, gas, and explosion proof.
References
Binder Singh, Paul Jukes, Ben Poblete, Bob Wittkower. 2010. 20 Years on lessons learned from Piper Alpha. The evolution of concurrent and inherently safe design. Journal of Loss Prevention in the Process Industries. Consulting e JP Kenny Inc., 15115 Park Row, 3rd Floor, Houston, TX 77084, USA Cameron, Houston, TX, USA.
Dennis hendershot. 2013. Process safety: Remembering Piper Alpha. Journal of Chemical Health & Safety, May/June 2013
