For some wire/cable insulation/jacket types, the polymer degradation can be tied to ozone exposure. Long term exposure can cause the insulation to become bridle and easily crack. There is also potential for conductor/shield corrosion with ozone exposure. For those using wire/cables in locations with potential for ozone exposure, understanding the impact of prolonged ozone exposure is necessary.
In the resistance to ozone test, a sample is placed in a heated enclosure with an atmosphere containing a prescribed amount of ozone; typically the ozone count is in the parts per billion range. After the exposure, the sample is removed and visually inspected for cracks. For a sample to ‘pass’ the test, no insulation cracks should be detected during the post-exposure visual inspection.