 North Sea crews typically worked two weeks on, two weeks off.Crews would often wait a day to a week to land on their platform, due to frequent dense fog which prevented landing on the 'Foggy Forties', a hazardous act even in clear weather.BP owned buildings near the airports around the North Sea to accommodate the crews while they were waiting or sometimes stranded in the Shetland Islands en route to the rigs from Aberdeen, Scotland.