Detection percentage is the probability that some type of test detects the failure mode. Detection percentage is calculated for parts and assemblies. While the range is supposed to be from 0 to 100, this is not enforced. You can insert Detection Percentage in the FMEA Tree Items table. The assembly FR is the sum of all mode failure rates for the assembly and all of its children. The assembly FR is zero for non-linked items in process or functional FMEAs.

The equation for calculating detection percentage is: