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Article from Marioff News 27, February 2008
-55°C and no fire brigade
Computer-generated image of the proposed Halley VI station,
courtesy of the
British Antarctic Survey and Hugh Broughton Architects
ANTARCTICA: An average temperature of -5 ºC in midsummer, -30 ºC in winter. Extreme maximum of +5 ºC. Extreme minimum of -55.3 ºC. Annual snow accumulation approximately 1 m. Gales on 40 days each year on average. In winter, total darkness for 55 days. Welcome to Antarctica, home to the British Antarctic Survey (BAS) since 1956 in the form of the Halley Research Station.
The Halley V Research Station is located on the Brunt Ice Shelf, a floating ice sheet 200 m thick, which is flowing towards the Weddell Sea at an accelerating rate and shedding a growing number of icebergs. There is a substantial risk that the station will be lost to a major iceberg “calving” event in the next ten years.
The BAS’s antarctic work is of global significance. It was from Halley that BAS scientists discovered the ozone hole in 1985. Since 1992 with the coming into service of the Halley V station, “Halley data” has been an intrinsic part of world-class research into atmospheric physics, geospace, atmospheric and snow chemistry, meteorology and ozone monitoring, and glaciology. The new Halley VI station will ensure that this indispensable work continues.
The design of the new Halley VI station is entirely modular, allowing pre-fabrication of the various components with the most modern composite materials. Movability is a key design criterion: the station will be relocated as needed in the face of the calving threat. Fire protection is another key design criterion.
The threat of fire is magnified in the Antarctic, where humidity is very low and there is no fire brigade to call. The loss of a structure can be very dangerous to personnel, particularly during the winter months when external temperatures are very low and there is no daylight. The structure of the Halley VI station has been fire-tested to the standards of the London Underground, with results showing that it can withstand a fire lasting for over 30 minutes – providing more than enough time for occupants to escape safely.
To alert station personnel if a fire starts, a comprehensive fire detection system is to be installed. Fire suppression will be provided throughout the station by the HI-FOG® Water Mist Fire Protection System comprising an SPU pump unit with closed sprinklers in the accommodation areas and open spray heads in the undercrofts and generators. Each station module is zoned and flexible hoses are supplied to allow the individual modules to be adjusted in height as the snow builds up during winter. The system is designed around the marine A800 tests, the most applicable for the layout. The HI-FOG® system’s small tubes and compact pumping module gave the architects room to flex their creativity in achieving an impressive station design. The Halley team starts on-site installation this winter.
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