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Focus: Major accidents

This is a tough, tragic and thought-provoking subject - and dwelling on it can be unpopular. But there are occasions when recalling and studying major accidents in the petroleum industry will be important and necessary. The 25th anniversary of Britain’s Piper Alpha disaster is one of them.

This article was originally published in
Safety - Status and Signals 2012-2013

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An explosive inferno on the UK platform claimed the lives of 167 people after a gas leak ignited. This accident on 6 July 1988 has  become engraved on the minds of everyone  working in and with the oil and gas sector as  one of the worst possible scenarios.

The memory of the incident off Scotland has been a heavy burden for Britain ever since. It has also left a deep mark on Norway’s consciousness, and ranks among the key events in the development of today’s NCS safety regime.

This is due not least to the fact that Magne Ognedal, the PSA’s retiring director general,played an important role at the Cullen inquiry on the Piper Alpha disaster.

The hearings and investigations conducted into this incident also became a point of reference, a touchstone and an acid test for Norway’s safety regulator, petroleum industry and regulations.

Norway was in a special position, since the Piper Alpha hearings took place when the country had just finished dealing with its own Alexander L Kielland tragedy.

This flotel capsized in 1980 close to the Edda platform in the Ekofisk area of the North Sea, killing 123 people - the worst disaster in Norwegian oil history.

A new safety regime was adopted in 1985 on the basis of the lessons learnt from Kielland, with a reorganisation of government regulatory responsibilities.

This system was put to the test in 1988.

Read how Norway’s model and new principles were treated in the Cullen report in this interview with him Magne Ognedal.

A major accident is defined as “an acute incident, such as a major discharge/emission or a fire/explosion, which immediately or subsequently causes several serious injuries and/or loss of human life, serious harm to the environment and/or loss of substantial material assets”.

Reducing the risk of such incidents is a key target of today’s Norwegian safety regulations. In addition to its human aspects, a major accident will have substantial social and socio-economic impacts.

However, the losses for those hit by these disasters are much greater than can be quantified in purely economic terms. No price can be put on the value of a human life.

Preventing major accidents represents the most vital of the PSA’s duties as a regulator. It works above all to prevent such disasters as Piper Alpha, Kielland, Deepwater Horizon, Montara, Texas City and Ekofisk Bravo.

The major accident perspective will always top its list of regulatory priorities, although this industry also has many other areas where supervision is highly important.

The PSA’s job is to influence the companies to operate in a way which prevents major accidents. Putting safety on the agenda, pressing for continuous improvement, helping to developregulations and enforcing them are its most important roles.

But it is solely up to the companies, including operators, licensees, vessel owners and contractors, to ensure that all their activities are pursued in compliance with the regulations.

This division of responsibilities is basic to Norway’s petroleum safety model. Activities are conducted by the companies, who must thereby ensure that these are safe and acceptable.

It must also be said that all the companies have the same goal as the PSA – on no account do they want accidents, which are also a burden on the industry. A disaster is the worst conceivable scenario.

Any disagreement which arises between government and industry concerns not the actual goal, but how the companies should work to achieve it.

Incidents with a major accident potential nevertheless occur every year in Norway’s petroleum industry, both offshore and in the land-based plants.

By potential is meant that the incident concerned, under slightly different circumstances, could have developed into a major accident. But very few such near misses have led to an actual disaster in Norway over the past 15-20 years.

If helicopters – which do not come under the PSA’s formal jurisdiction – are included, the crash off Brønnøysund in 1997, with the loss of 12 lives, was the last major fatal accident in the Norwegian petroleum sector.

The most recent such incident on an offshore facility occurred in 1985, when the mobile West Vanguard unit suffered a shallow gas blowout.

Because of its financial impact was high, the 2009 collision between Big Orange XVIII and an Ekofisk installation is also viewed as a major accident. But no people were injured or killed, even though a potential for such an outcome was present.

A number of technical, operational and  organisational factors can individually or collectively cause an accident and influence its development.

But the question is how the industry and the authorities work to prevent major mishaps and monitor risk in the Norwegian petroleum industry.

This is first and foremost a matter of risk understanding and management in the companies, work to reduce uncertainty, and ensuring good emergency preparedness.

Where the government is concerned, keeping the level of risk in the industry under surveillance provides the basis for influencing safety.

The PSA’s annual RNNP survey plays a key role in this work, not least by identifying and monitoring developments in the areas where the probability of major accidents is highest.

Four defined hazard and accident conditions (DFUs) in the RNNP account for roughly 80 per cent of the overall major accident risk on the NCS.

These are oil and gas leaks, serious well incidents, ships on a collision course, and damage to support structures and maritime systems.

Hydrocarbon leaks with consequent fires and explosions are the biggest contributor to major accident risk at Norway’s land-based petroleum plants.

Helicopter transport also has a major accident potential but is excluded from the RNNP becauseit is regulated by the Norwegian Civil Aviation Authority. However, it and the PSA collaborate closely on relevant issues and challenges.

The RNNP does not provide the only basis for the PSA’s monitoring of developments in risk level. The latter also draws on experience from its audits, for instance.

Other sources include company reports on accidents and near misses, investigations of major incidents, and research and development activities.

All this adds up to an overall view of trends in the risk picture. That it turn says a lot about which areas should be prioritised by regulator and industry in reducing the probability of major accidents and serious incidents.

A fairly academic definition of risk calls it “the combination of possible future incidents and the consequences of these, with associated uncertainty”.

This can be popularised by saying that no activity can be pursued without risk - in other words, without some uncertainty about its possible outcome.

Identifying risk is the starting point for all safety work, including knowledge of possible accident scenarios in the relevant activity and their consequences.

An understanding of risk is essential for preventing accidents, for establishing appropriate emergency preparedness and for reducing uncertainty.

But risk is never static. Many factors contribute to influencing and developing an understanding of it, including learning from accidents.

Experience from earlier errors and successes also plays a part, while introducing new technology is significant - along with advances in working methods and updating In other words, risk can naturally and fortunately – be managed.

In recent years, the PSA has given particular emphasis to management and major accident risk among the clutch of main priorities Major accidents are the scenario which the regulator devotes the largest portion of its time and resources to preventing – and the one it fears the most. And that is the way all players in the petroleum industry must think.

This naturally reflects a very conscious choice, which emphasises the reality that managers have a particular responsibility for controlling major accident risk.

All initiatives and decisions backed by senior executives will define and influence the conditions which affect such hazards in a company.

The PSA expects management at all levels to work to reduce major accident risk and to ensure that these efforts are pursued in a carefully planned manner. They must establish clear goals and make sure that all company activities are covered.

In other words, preventing major accidents is more than a main priority for the government. It is the most important issue of them all, which is always at the top of the PSA’s agenda.