In Reply to Parent Post by qq130230416
i have a question, why RPN is S*O*D? what is meaning for this formula?
S = Severity
O = Occurrence
D = Detection
Severity is how "bad" the injury would be if there was a failure (1=none, 10=death)
Occurrence is how likely is the defect to occur (1=unlikely, 10=often)
Detection is how likely are your controls to detecting the defect should it occur (1 = Always detected, 10 = never detected)
You rate each failure mode on a rating of 1 to 10 for each of the three. Multiply the ratings to get the RPN for the failure mode.
A flaw with this rankin is that a failure mode with very low severity, high occurrence with low detection would score an RPN of 100, while a failure mode with high severity, low occurence and low detection would also score a 100. I favor a rating system that weights the severity more than detection.