Gas/Vapor-Tight Cables for Class I Hazardous Locations

The National Electrical Code (NEC) provides for reduced sealing requirements on-multiconductor cables in Class I hazardous locations when the cable has a gas/vapor-tight continuous sheath and will not transmit gases or vapors through the cable core. The new cables that comply with this requirement are discussed, together with the reduced sealing requirements and the testing procedure to verify compliance of the cable with the gas/vapor blocking requirements.