Specifies the procedure for testing the resistance to vertical flame propagation for a single small vertical electrical insulated conductor or cable, or optical cable, under fire conditions. The apparatus is given in IEC 60332-2-1. This standard gives the procedure for testing small optical fibre cables or a small insulated conductor or cable when the method specified in IEC 60332-1-2 is not suitable because some small optical fibre cables may break or small conductors may melt during the application of the flame. The recommended range of application is for the testing of small single insulated conductors or cables of less than 0,5 mm2 cross-section. NOTE - Since the use of insulated conductor or cable which retards flame propagation and complies with the recommended requirements of this standard is not sufficient by itself to prevent propagation of fire under all conditions of installation, it is recommended that wherever the risk of propagation is high, for example, in long vertical runs of bunches of cables, special installation precautions should also be taken. It cannot be assumed that because the sample of cable complies with the performance requirements recommended in this standard, that a bunch of cables will behave in a similar manner. (See IEC 60332-3 series.) Recommended requirements for performance are given in Annex A. Has the status of a group safety publication in accordance with IEC Guide 104.