Human fault

A primary source of critical system malfunction is related to human faults.

The nature of human faults

People instigate errors spontaneous. Typically, they are not aware of making the error. When the are aware of the error, they do not understand the reason why they made it.

Types of human faults

• Omission - avoidance ( Example )
• Slip - Commission of a wrong action

The operator's awareness of errors

The operators' awareness of the situation is typically dynamic and ambiguous. Two extremes in the scale of operator's awareness of the situation

• Mistake : Intentional action or avoidance, such due to wrong perception of the system state (in case of exceptional situation).
• Unintentional action ( Slip ) or avoidance ( omission).

Human reliability

Human reliability can be defined as the reciprocal of the rate of human faults.

For example

Suppose that the rate of operator faults is 10 faults per minute.

Then the reliability is measured by the MTBF = 6 seconds

Related topic

Updated on 09 Mar 2017.