Section 6.2.3.5 of ISO 19642-2 specifies the screening attenuation test using the tri-axial method, complementing the absorbing clamp method of section 6.2.3.4.
The tri-axial method provides screening attenuation measurements in a controlled test environment, useful for comparing cable shield performance across different constructions and manufacturers.
IEC 62153-4-4 specifies the test method for measuring the screening attenuation (shielding effectiveness) of cable screens used in metallic communication cables.
The test typically uses a tube-in-tube measurement method where the shielded cable is placed inside a test fixture and the ratio of electromagnetic energy transmitted through the shield versus the incident energy is measured across a range of frequencies. Results are expressed in decibels.
Screening attenuation measurements are essential for cables used in electromagnetic compatibility (EMC) sensitive applications including aerospace, military communications, and data transmission systems where shielding integrity directly affects signal quality.