1.1 This specification covers cold-formed welded high strength carbon steel or high-strength low-alloy steel Hollow Structural Sections (HSS) or special shape structural tubing for welded, riveted, or bolted construction of bridges, buildings, and for structural purposes. 1.2 This HSS is produced in welded sizes with a periphery of 64 in. [1626 mm] or less, and a specified wall thickness of 0.625 in. [16 mm] or less. Note 1: Products manufactured to this specification may not be suitable for those applications such as dynamic loaded elements in welded structures, etc. where low-temperature notch-toughness properties may be important. Inquire if dynamic loaded elements are required. 1.3 The text of this specification contains notes and footnotes that provide explanatory material. Such notes and footnotes, excluding those in tables and figures, do not contain any mandatory requirements. 1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order. 1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.