T-276.2 Size. The designated hole penetrameter with
essential hole or designated wire diameter shall be as
specified in Table T-276. A smaller hole in a thicker
penetrameter or a larger hole in a thinner penetrameter
may be substituted for any section thickness listed in
Table T-276, provided equivalent penetrameter sensitivity
(EPS) is maintained and all other requirements for
radiography are met. Approximate equivalence between
hole and wire penetrameters is shown in Table B-220
of Article 2, Nonmandatory Appendix B, and may be
used to determine approximate equivalence between
hole penetrameters.