Specifies the test apparatus to be used for testing cables required to maintain circuit integrity when subject to fire and mechanical shock where the test condition is based upon a flame with a controlled heat output corresponding to a temperature of a nominal 850 °C. It is intended for use when testing cables of greater than 20 mm overall diameter. It also provides, in annex A, the method of verification of the burner and control system used for the test. Has the status of a group safety publication in accordance with IEC Guide 104.