Significance and Use 14.1 Twist Test—This test is designed to detect surface related issues such as flaking or cracking in the shell as well as core integrity of the wire related to elongation. Failures under the specified requirements could lead to insulation failures allowing moisture and other factors to affect wire performance. 14.2 Reverse Torsion—This test is designed to detect copper and core steel bonding issues which could lead to corrosion and eventual signal failure through the wire.Scope 1.1 This specification covers bare round 21 % conductivity copper-clad steel wire for the center conductor in tracer wire, also known as locating wire. 1.2 Two grades of copper-clad steel wire are covered as follows: 1.2.1 21EHS: Nominal 21 % Conductivity Extra High Strength 1.2.2 21EHS-A: Nominal 21 % Conductivity Extra High Strength-Annealed 1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 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.
