The 25 cases of oil well blowout, which happened in the oil field in China from 1962 to 1993[1], were analyzed. some conclusions about the factors related to the human error are drawn from the statistic data. The peak of the blowout frequency happened on Monday or Friday during the week and around 3:00am during the day. These are possible related to the disturbance of circadian rhythm. Because the management error, especially the human error, is one of the major factors in the oil well blowout accidents. However, the least of the blowout frequency happened on Wednesday. From these conclusions, we call learn a lesson of proper arrangement in the schedule of duty in drilling operations. A training program of the well blowout operation and methods of prevention will be provided to drilling operators, in order to improve their ability of dealing with the blowouts and avoiding the misoperation due to the short limited time before making a right decision.
Studies of actuarial records of industrial experience have shown that human-system interactions are extremely important to safety, However, the oil and gas production industry which maybe is not so commonly well known, is indeed a potentially dangerous one due to its nature. A study by McNabb el al [2] in 1994 found that non-fatal injuries among field workers in this industry were 49% higher than among workers in all other US industries combined, and that these injuries were more severe. The drill occupation is acknowledged as being one of the more dangerous within this industry, and therefore worthy of efforts to reduce the well blowout rate.
Theories of how accidents are caused have endured four stages of development. The first stage existed at the period of time when developments in technology were rapid and the majority of accidents were caused by technological malfunctions. The second stage focused on human error where blame and responsibility were assigned to the person directly involved in the unsafe act. The third stage involved understanding why people behave in the way they do and delving deeper to understand the cause of accidents. The last one focused on the contribution of management to safety [3].
Now in order to obtain the underlying causes of these accidents and demonstrate what types of human error were involved in these blowouts. Six [4] of the 25 cases of blowouts were analyzed in detail, some statistics data were analyzed of the 25 blowouts, Some conclusion were drawn.
While documents of the six blowouts of the 25 cases were analyzed in details, an attempt was always made to work back to the fundamental human error which contributed to the failure. A failure code was then allocated to each possible type of error [5]. Only if a failure could not be directly attributed to a human error was given the code E, for equipment failure. Human error leading to equipment failure could be of five different types: Design error (D), Operating error (O), Production error (P), Management error (M), Testing error (T).
