Factors for Tolerance Limits which Control Both Tails of the Normal Distribution
D. B. Owen, William H. Frawley · Journal of Quality Technology · 1971
A special type of tolerance limits for a normal distribution is presented. The limits have the property that with probability γ no more than a specified proportion p1 of a normal population is below the lower limit and at the same time no more than a specified proportion p2 of that population is above the upper limit. An extensive tabulation of the factors necessary to calculate these limits is provided.