5.2.1 The test must be carried out on a representative
sample of cargo. Before being tested for resistance to detonation, the whole mass of the
sample is to be thermally cycled five times between 25°C and 50°C (± 1°C) in sealed
tubes. The sample shall be maintained at the extreme temperatures, measured at the
centre of the sample, for at least 1 hour during each thermal cycle and at 20°C (± 3°C)
after complete cycling until tested.