(a) Uncertain;
(b) Likely to deteriorate in service before normal replacement; or
(c) Subject to appreciable variability because of uncertainties in manufacturing processes or inspection methods.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25–23, 35 FR 5674, Apr. 8, 1970]
NEXT: Sec. 25.621 - Casting factors.
PREVIOUS: Sec. 25.613 - Material strength properties and material design values.