Does data on reliability tell us about equipment or people?

Abstract

Many failures, particularly of mechanical equipment, are due, not to inherent weaknesses in the equipment but to poor installation or maintenance or to misuse. The failure rate can thus vary greatly between one organisation and another and tells us little about the equipment, more about the people who maintain and operate it. Examples considered include bellows, pipelines, machinery, non-return valves and furnaces. The failure data may still be useful as a guide to action; it may show which equipment cannot withstand poor installation, maintenance or operation and is therefore best avoided when possible or it may indicate a need for better training or auditing. In some cases suppliers should provide more information on installation or maintenance procedures or conditions of use.