(a) The tensile strength and percentage elongation shall be determined from test pieces of gauge lengths preferably equal to L_o=5.6(A_o)^1/2 (see regulation 16). Alternatively, other gauge lengths may be used, provided the elongation is expressed as the equivalent value on a gauge length of 5.65(A_o)^1/2.

(b) In arbitration cases, a test piece of gauge length equal to 5.65(A_o)^1/2 for rectangular test piece or 5 d_o for round test pieces shall be used. For plate thickness exceeding 60mm, test pieces shall be taken from the exterior third of the plate cross section. Wherever practicable, the rolled surface shall be retained on two opposite sides of the test piece.