TMI was operator error.... but:
The design made it very easy to commit this error. An operator turned a switch to open the water valves.... after which the system indicated that the valves were "open". In fact, one of the valves had jammed shut. The system was only designed to indicate the the command was given for the valves to open - not their actual position!!! So it was easy for the operator to be deceived.
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TMI was operator error.... but: The design made it very easy to commit this error. An operator turned a switch to open the water valves.... after which the system indicated that the valves were "open". In fact, one of the valves had jammed shut. The system was only designed to indicate the the command was given for the valves to open - not their actual position!!! So it was easy for the operator to be deceived.