1.1 This specification covers only factory-made wrought aluminum and aluminum-alloy welding fittings in contrast to field-made fittings. The term "welding fittings" applies to butt-welding or socket-end parts, such as 45° elbows, 180° return bends, 90° short radius elbows, and other types made to the dimensional standards specified by ASME B16.9 and B16.11. Note 1 -Throughout this specification use of the term alloy in the general sense includes aluminum as well as aluminum-alloy. 1.2 For acceptance criteria for inclusion of new aluminum and aluminum alloys in this specification, see Annex A1. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and heal practices and determine the applicability of regulatory limitations prior to use.