Section 6-77-31 - Nominal wall thickness (t) for steel pipe(a) If the nominal wall thickness for steel pipe is not known, it is determined by measuring the thickness of each piece of pipe at quarter points on one end.(b) However, if the pipe is of uniform grade, size, and thickness and there are more than ten lengths, only ten percent of the individual lengths, but not less than ten lengths, need be measured. The thickness of the lengths that are not measured must be verified by applying a gauge set to the minimum thickness found by the measurement. The nominal wall thickness to be used in the design formula in section 6-77-29 is the next wall thickness found in commercial specifications that is below the average of all the measurements taken. However, the nominal wall thickness used may not be more than 1.14 times the smallest measurement taken on pipe less than twenty inches in outside diameter, nor more than 1.11 times the smallest measurement taken on pipe twenty inches or more in outside diameter.[Eff ] (Auth: HRS § 269-6) (Imp: 49 C.F.R. §192.109, OCT 1, 1990)