The Piper Alpha Incident 25 Years on:
On the 6th July 1988, a series of events began, which led to a number of massive explosions and the death of 167 oil workers on the Piper Alpha Oil rig, in the North Sea, 120 miles north of Aberdeen.
Above: Roy Thomson, Piper Alpha Survivors account.
Two pumps were used for pumping condensate which contained methanol and methane (natural gas) back to shore. Only one pump was used at a time and one pump (Pump A) had been shut down for routine maintenance. Pump A also had a safety valve removed for testing and the hole that was left in the pipe was covered with a blanking plate (called a blind flange) but the bolts were only loosely tightened.
Later that day the shift running the Oil Rig then changed to the night shift at 6pm as usual.
The pump that was working, Pump B, broke down at 21:45 that day. As the fuel used for powering the oil rig came from methane provided by Pump B, the workers only had a short time to rectify the problem.
Above: Piper Alpha in fire.
In the panic the workers started getting Pump A ready to start and removed the electrical and mechanical isolation. They did not realise the safety valve had been removed and blanked by the day shift as this was out of view, quite a way from the pump. The documentation completed by the day shift communicating this to the night shift was never found.
At 21:55 the workers started up Pump A and methane (natural gas) was heard hissing out of the pipe, where the safety valve had been removed. Shortly after this, the first explosion occurred when the leaking methane gas ignited. Within minutes of the first explosion, the incident escalated out of control and within hours the whole oil rig was completely destroyed and 167 people were killed.
Two connected oil rigs, in the same oil field, continued pumping into the same pipeline as Piper Alpha for hours after the first explosion, even though they could see Piper Alpha still on fire in the distance. The managers on these rigs were too frightened to close down production, as this would have cost hundreds of thousands of pounds in lost production and they could have been in serious trouble. This in-action significantly worsened the whole incident as all the oil they were producing was coming out on the Piper Alpha rig and burning too.
Many of the improvements in health and safety procedures developed after the Piper Alpha explosion have been applied to lower risk industries as best practice: management of change, permits to work, hot work permits, isolation permits and lock off, tag off, all have their place in industry, not just the the oil, gas and petro-chemical industries. The use of intrinsically safe equipment, where explosive atmospheres may occasionally be present, is also a legal requirement under the Dangerous Substances Explosive Atmosphere Regulations 2002 (DSEAR.)
This incident demonstrates how complacency and poor adherence to safety laws and procedures can cause a chain of events which escalate out of control very quickly. I don't imagine anyone working on the oil rig ever imagined that something of this magnitude could have ever "happened to them."
See other articles and links below:
http://en.wikipedia.org/wiki/Piper_Alpha
http://www.iosh.co.uk/about_us/what_were_up_to/piper_alpha_%E2%80%93_25_years_on.aspx
http://news.bbc.co.uk/onthisday/hi/dates/stories/july/6/newsid_3017000/3017294.stm
This last link is particularly poignant:
http://news.bbc.co.uk/onthisday/hi/witness/july/6/newsid_3036000/3036510.stm
Picture Below: Piper Alpha Still smouldering