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…tolerance factors, kA, for the normal distribution
The exact computation of kB values is 1
n times the 0.95th quantile of the noncentral
t-distribution with noncentrality parameter 2.326 n and n − 1 degrees of freedom (Reference
11). Since this is not a calculation that Excel can handle easily, the following approximation to
the kB values is used:…
https://www.wichita.edu/industry_and_defense/NIAR/Research/cytec-mtm45-1/3K-PW-G30-500-Fabric-3.pdf