This paper presents a novel statistical characterization of the indoor low-voltage (LV) narrowband power line communication (PLC) channel in CENELEC and FCC/ARIB bands. Experimental measurements of electrical network complex transfer functions were used to determine, for the frequency range up to 500 kHz, the statistics of the average channel gain, the delay spread parameters, the coherence bandwidth and the channel capacity. The average measured channel attenuation exhibits values between 16.36 and 26.95 dB with a mean of 20.75 dB in the frequency band from 10 to 500 kHz. The root mean square (rms) delay spread has a mean value of 2.12 mu s with 90% of the channels revealing values below 3.20 mu s. The minimum coherence bandwidth at 0.9 correlation level is of 1.23 kHz and the mean channel capacity is of 5.32 Mbps. The lognormal behavior is confirmed and justified for the rms delay spread but not for the average channel gain. The negative correlation between these two parameters is examined, and the relationships between the different studied metrics are also explored.