IEC 61300-2-17:2010 details a procedure for determining the suitability of a fibre optic device to withstand environmental conditions of extended low temperature (cold), which may occur in use, storage and/or transport. This procedure does not assess the ability of a device to operate during temperature variations; in this case, IEC 61300-2-22 would be used. The main changes with respect to the previous edition are: - Procedure and details to be specified were reconsidered; - The deviation of the temperature in severity was changed ± 3 °C to ± 2 °C.