Gas Tight test
Restricted breathing cable suitable for installation in explosive areas must prevent gas or vapour migration through the interstices between individual cores when the cable leads to a non-hazardous area or between different zones.
The requirement of IEC 60079-14 ANNEX E specifies that a cable with a length of 0,5m should be type tested when installed into a sealed enclosure of 5 l.
The cable is considered acceptable if the time interval required for an internal overpressure of at least 0,3 kPa to drop by 0,15 kPa is not less than 5 s.