Drilling deeper but safely

Maintaining standards in a difficult environment

By Morand Fachot

Offshore drilling is a particularly dangerous activity in which a harsh environment is combined with hazardous substances and operational equipment that is capable of causing fires or explosion. Safety on offshore installations relies largely on the proper and safe interaction of equipment and human factors. IEC TC (Technical Committee) 18: Electrical installations of ships and of mobile and fixed offshore units, prepares International Standards for the industry.

Offshore platform in the North Sea (Photo: Statoil) Offshore platform in the North Sea (Photo: Statoil)

Equipment failures…

25 March 2012: a gas leak forces the evacuation of the Elgin offshore platform in the North Sea; all on board are evacuated. It may take up to six months to halt the flow of oil and gas from the well and will cost billions of dollars in lost production and clean-up, the operator says.

21 April 2010: an explosion on a semisubmersible offshore platform in the Gulf of Mexico kills 11 and injures 16. Some 5 million barrels of oil are released, costing tens of billions of dollars in compensation and clean-up expenses.

These two disasters, resulting from equipment or installation failures, illustrate the major risks and costs that may be encountered in the operation of offshore rigs. Many other less serious accidents, which do not halt production, cause environmental damage, result in many human deaths or inflict severe injuries, go largely unreported.

Thirst for fossil fuels fuels industry

Offshore crude oil production, which started in the 1940s, has grown 25-fold since the 1960s to become the main source of growth for world oil production. Onshore extraction from mature fields inland has essentially reached a plateau during the last two decades. Natural gas is the world’s fastest growing fossil energy source; a significant share of production is also being met by offshore installations.

This expansion of the sector drives the construction of offshore units. In 2010, there were 767 rigs, with 59 more projected for 2011, according to the IUMI (International Union of Marine Insurance), the international body of national and marine insurance associations and professionals. Damage claims for losses are growing as a direct result of the surge in the construction of more units to meet the demand for deep-water drilling.

When safety is an issue: call in the IEC!

Proper electric installations are absolutely central to the safe operation of offshore units; IEC TC 18 develops International Standards for such installations in collaboration with IMO (International Maritime Organization). The seven standards in the IEC 61892, Mobile and fixed offshore units - Electrical installations series are "intended to enable safety in the design, selection, installation, maintenance and use of electrical equipment for the generation, storage, distribution and utilisation of electrical energy for all purposes in offshore units, which are being used for the purpose of exploration or exploitation of petroleum resources". The series "is based on equipment and practices which are in current use, but it is not intended in any way to impede the development of new or improved techniques".

Latest additions raise offshore safety

Two standards in the 61892 series were released in March 2012. The second edition of IEC 61892-2 contains provisions for all aspects of System design for offshore installations. The third edition of IEC 61892-3 deals with Equipment, covering everything from generators and motors to transformers, from switchgear and control gear assemblies to secondary cells and batteries, or from communication and control to underwater systems, to name just a few.

The scopes for both International Standards indicate that they apply "to equipment in all installations, whether permanent, temporary, transportable or hand-held, to a.c. installations up to and including 35 000 V and d.c. installations up to and including 1 500 V (...)". Both also "set requirements for equipment, which are additional to the requirements given in the product standard for the relevant equipment".

Updated standards maintain standards

The 7 standards of the 61892 series meet the IMO's MODU Code (Code for the construction and equipment of mobile offshore drilling units) and are currently referenced by only 3 national regulatory bodies, but they are widely used by oil companies and major drilling contractors. The latest addition will ensure the series remains up to date and will contribute to greater safety in the offshore industry, at least in one of its aspects, as it depends on many factors other than electrical safety alone.

Offshore platform in the North Sea (Photo: Statoil) Offshore platform in the North Sea (Photo: Statoil)
Deepwater Horizon offshore installation on fire, Gulf of Mexico, April 2010 (Photo: US Coast Guard) Deepwater Horizon offshore installation on fire, Gulf of Mexico, April 2010 (Photo: US Coast Guard)
Andrew production platform (Photo: BP p.l.c.) Andrew production platform (Photo: BP p.l.c.)