1.1 This specification covers two grades, 36 [250] and 50 [345] of rolled steel structural shapes and plates with low yield to tensile ratio for use in building framing or for general structural purposes.

1.2 All shape profiles with a flange width of 6 in. [150 mm] and greater described in Specification A 6/A 6M Annex A2 and plates up to and including 5 in. [125 mm] thick are included in this specification.

1.3 Supplementary requirements are provided for use where additional testing or additional restrictions are required by the purchaser. Such requirements apply only when specified in the purchase order.

1.4 When the steel is to be welded, a welding procedure suitable for the grade of steel and intended use or service is to be utilized. See Appendix X3 of Specification A 6/A 6M for information on weldability.

1.5 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system is to be used independently of the other without combining values in any way.

1.6 The text of this specification contains notes or footnotes, or both, that provide explanatory material; such notes and footnotes, excluding those in tables and figures, do not contain any mandatory requirements.