Managing Explosion Risk in Arctic Areas

Explosion risk is a major concern in Arctic areas. Platform modules are traditionally built with open ends, providing natural ventilation that can help prevent the accumulation of a flammable gas cloud in the case of a gas leakage as well as reduce explosion pressure. In Arctic areas, however, open-end designs may have a negative effect on the working environment due to a high wind chill factor. This may lead to periods where workers are unable to perform maintenance operations, which in turn may result in production losses. In addition, open-end designs may pose problems with regard to icing of equipment.

In light of all this, it would seem that a closed-end module with explosion panels at the module ends to reduce the flow of cold air would be the natural design choice. However, studies have shown that introducing a closed module design will lead to a higher frequency of ignition of gas leakages and higher explosion pressure due to gas accumulation inside the enclosed module, thus resulting in a higher level of fire and explosion risk. This increased explosion risk will necessitate designs that can withstand a higher accidental load on structural elements, and this in turn will raise construction costs.

Scandpower performed a generic explosion risk study for Arctic platform concepts in collaboration with StatoilHydro’s research department, based on Scandpower’s in-house tool for probabilistic explosion risk modeling. The project resulted in an alternative to a closed module design, which may reduce explosion risk while at the same time providing a satisfactory working environment in Arctic areas. The concept features rotating wall elements, which, when gas is detected, have the potential to reduce the strong explosion frequency by a factor of three compared to closed module designs. Scandpower presented the research at the Ninth SPE International Conference on Health, Safety, and Environment in Oil and Gas Exploration and Production held in Nice, France, on April 15-17, 2008. The complete paper is available here (pdf).

Thanks to the extensive expertise generated during this project, Scandpower can provide the oil and gas industry with high-quality decision-making support on technical safety issues in Arctic environments.