The July 6, 1988 the oil platform Piper Alphalocated in the North Sea near the coast of Aberdeen, Scotland suffered a devastating fire which caused 167 victims165 platform workers (out of 226 total) and 2 rescue workers. It is, still today, the deadliest accident never recorded on an oil rig. Subsequent investigations highlighted a chain of problems, from incorrect design to human errors, combined with an excessive workload, structures inadequate to manage the high quantities of oil treated and to reduced maintenance by the company Occidental Petroleum and to one “relaxation” of authorities’ controlswhich contributed to making the safety measures ineffective and hindering the evacuation of the crew.
The Piper platform and its connections
The Piper Alpha platform was part of an extraction system offshore (off the coast) at the northern tip of the United Kingdom, and represented a crucial oil distribution hub. This platform sent the oil extracted towards the island of Flotta, one of the Orkney Islands, home to an important oil port currently controlled by the company Repsol Sinopec Resources UK Limited; at the same time, treated the extracted gas from its deposit and that received from the neighboring platforms (the Tartan and the Claymore) to send it towards the MCP-01 compressor stationin turn connected to the port of Saint Fergus near Aberdeen.
The entire structure had evolved over time to catch up increasingly higher production rates of the platform and those connected, leading to extreme compactness: the gas treatment and oil storage modules were extremely close to crew facilities and platform control.
The accident: explosions and fires on board the extraction platform
The platform provided, from a security perspective, several “redundant” systemsa term that indicates the presence of two elements with the same function. Unfortunately, in production environments the presence of twin elements is sometimes used to continue activities in case of maintenance, which is a behavior eliminates the safety feature.
During the day shifts on 6 July, work had been carried out in the gas compression module “C”: this led to the shutdown of the main pump “A” and the removal of a safety valve for repairs, thus making its use dangerous. These morning shift interventions, they didn’t come reported directly to the team of night shiftbut simply annotated on two different modules.
After a few hours, a fault stopped pump “B” and the night team, unaware of the danger, tried to reactivate pump “A”: the lack of the safety valve and the insufficient closure of a flange in the pipes led to a gas accumulation in module C.
Gas yes fireprobably due to contact with hot surfaces or due to a electrostatic dischargeleading to first explosion which immediately damaged the neighboring modules D (technical rooms which contained, among other things, the diesel fire safety pumps) and the separation module B, where a second explosiondue to the presence of crude oil.
With the destruction of fire safety wallsinadequate to withstand explosions of this magnitude, the flames quickly spread to the upper deck towards the storage modules, where they were stored 1200 barrels of fuel . The high temperatures also led to breakage of the gas main arriving from the Tartan platform: from this, the high pressure gas generated a further “jet” fire at the bottom of the platform, filmed live by a camera, as evidenced by this video.
Lack of electricity and coordination with other platforms
The destruction of the technical rooms prevented the use of the fire pumps kept inside them, also depriving the structure of electricity and the second security system, this time electric. In reality, the latter should have been activated automaticallybut it had been deactivated for security reasons: given that this system collected water from the sea, the operating procedures required stop it during the operations of the underwater personnel, in action that night. The lack of electricity it also made manual activation impossible of this second safety system.
The lack of electricity had further consequences: was not sent no alarm to the modules where the staff stayed, and the communications with the emergency services and the nearby platforms they were hindered.
Because of the poor coordinationbut also of the very high costs of a “production stoppage”, sending gas from connected platforms it was not immediately stopped. If the nearest Tartan platform interrupted the connection independently and quickly, from the more distant Claymore the flow of gas continued to arrive at Piper in the hope that the safety systems would contain the first fires. The sending was only interrupted 1 hour laterwhen one fourth explosion led to the collapse of the structure. Several modules, including staff quarters, fell into the sea following this blast, taking dozens of workers with them.
Delays in rescue and evacuation
Subsequent investigations highlighted theunpreparedness of the platform supervisor (IOM), who lost his life in the accident and, according to witnesses “he fell into a state of shockwas unable to organize a difficult evacuation”. Chronic lack of staff, flash staff promotions unprepared to cover roles of responsibility and an excessive workload were certainly among the major causes of the disaster.
Of the 226 workers present on the platform, only 61 managed to escape deciding, in the absence of precise orders, to evacuate the platform throwing himself into the darkness and in the cold of the North Sea from the different levels, including the helipad at well 50 meters high.
There poor attention and surveillance by the English authoritiesfavored by neo-liberal policies and the enormous profits deriving from the oil sector, contributed to the low safety standards on English platforms: the situation was already reported in a published book in 1982 with the prophetic title “The other price of British oil: security and control in the North Sea”, a complaint which however went unheeded.
