This paper presents ultra-wide-band measurements of impulsive noise within an electricity substation compound. The measurements are made in four contiguous frequency bands covering the range 100 MHz to 6 GHz. This range includes those bands relevant to modern wireless LAN and wireless PAN technologies such as IEEE 802.11a/b/g and IEEE802.15.1/4. Impulsive events are extracted from the measured data. A noise amplitude distribution analysis of these events is presented.