Fire Testing
Circuit Integrity
7. Circuit (insulation) Integrity in accordance with BS 8491:2008
BS8491:2008 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. This standard is related to cables
included in BS 7346-6 and certain other active fire safety systems. It is applicable to cables of rated voltage not
exceeding 600/1000V and overall diameter greater than 20mm. The test method in BS 8491-2008 includes
subjecting the cable under test to radiation via direct impingement corresponding to a constant temperature
attack of 842°C, to direct mechanical impacts corresponding to a force of approximately 10N and to direct
application of a water jet simulating a water fire fighting jet. The test method given in this standard includes
three different test durations to allow testing of cables intended for different applications.