A Comparison of Failure Rates

Failure rates obtained from industry databases, manufacturer FMEDA analysis, manufacturer field failure studies, company failure records or other sources can be compared. The results will be different as described above. 

Generally, less specific data turns out to be more conservative and that is appropriate for safety verification purposes following the rule that the less one knows, the more conservative one must be. Remember that industry databases may include systematic failures, multiple technology classes, wear out failures and possible multiple reports per failure. These issues naturally cause the numbers from such sources to be high. 

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