This Recommendation considers continuous electromagnetic phenomena from 9-150 kHz. Impulsive low frequency phenomena are considered in other K-series Recommendations. Continuous phenomena above 150 kHz are covered by [ITU-T K.48]. Both the emissions of and the immunity to induced signals at frequencies from 9-150 kHz are taken into account in this Recommendation. This Recommendation defines test set-up@ measurement methods@ emission limits and immunity test levels for telecommunication network equipment. This Recommendation applies to all types of telecommunication network equipment. Due to the nature of the interference@ the immunity test is applicable only to equipment having an analogue voice interface that could be influenced by disturbing signals in the voice frequency range.