At its peak, the Piper Alpha oil platform was producing 300,000 barrels of oil a day, or 10% of Britain's total oil production from just one platform. In 1980, the platform was modified to drill for natural gas in addition to oil. In 1988, the rig was due for major maintenance and upgrades. The operator, Occidental Petroleum, made the decision not to shut production down during this work. When a safety valve was removed for scheduled repairs it initiated a series of errors and events that led to a number of massive explosions that took the lives of 167 workers or three-quarters of the crew.