[2] [2] British Standards Institution. Test method for resistance to fire of cables required to maintain circuit integrity under fire conditions: BS 6387-2013 [S]. London: British Standards, 2013: 4.

[3] [3] International Electrotechnical Commission. Tests for electric cables under fire-conditions-circuit integrity-part1: test method for fire with shock at a temperature of at least 830℃ for cables of rated voltage up to and including 0.6/1.0kV and with an overall diameter exceeding 20mm. IEC 60331-1-2018[S]. Geneva: Group Safety Publication, 2018: 7.

[4] [4] International Electrotechnical Commission. Tests for electric cables under fire-conditions-circuit integrity-part2: Test method for fire with shock at a temperature of at least 830℃ for cables of rated voltage up to and including 0.6/1.0kV and with an overall diameter not exceeding 20mm. IEC 60331-2: 2018[S]. Geneva: Group Safety Publication, 2018: 7.

[5] [5] International Electrotechnical Commission. Tests for electric cables underfire-conditions-circuit integrity-part21: procedures and requirements-cable of rated voltage up to and including 0.6/1.0kV.IEC 60331-21-2018 [S]. Geneva: Group Safety Publication, 2018: 8-9.

[6] [6] British Standards Institution. Method for assessment of fire integrity of large diameter power cables for use as components for smoke and heat control systems and certain other active fire safety systems:BS 8491-2008 [S]. London: British Standards, 2008: 1-2.