1.1 This practice is intended as a guide for standardizing eddy-current equipment employed in the examination of seamless aluminum-alloy tube. Artificial discontinuities consisting of flat-bottomed or through holes, or both, are employed as the means of standardizing the eddy-current system. General requirements for eddy-current examination procedures are included. 1.2 Procedures for fabrication of reference standards are given in Appendixes X1.1 and X2.1. 1.3 This practice is intended for the examination of tubular products having nominal diameters up to 4 in. [101.6 mm] and wall thicknesses up to the standard depth of penetration (SDP) of eddy currents for the particular alloy (conductivity) being examined and the examination frequency being used. Note 1 -This practice may also be used for larger diameters or heavier walls up to the effective depth of penetration (EDP) of eddy currents as specified by the using party or parties. 1.4 This practice does not establish acceptance criteria. They must be established by the using party or parties. 1.5 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.6 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.