The long gap length experiments were performed in chamber of dimensions 2.5 m x 2.5 m x 2.5 m and is shown in Figure 2. Figure 2b illustrates the chamber schematic while Figure 2c shows a picture of the electrodes used for the rod/plane gaps. The following three electrode configurations were used to create non-uniform fields: hemispherical rod/plane, conical rod/plane and rod/rod. All the rod designs and their dimensions are shown in Figure 3. The electrodes were of Grade 304 stainless steel and were polished using polishing wheels of 1000 grit. The important dimensions of the electrodes are shown in Figure 3. For the short gaps, the grounded plane electrodes had a diameter of 15 cm, while the long gaps used a 131 cm diameter ground plane. The size of the grounded plane was varied to be in accordance with IEEE Std. 4 requirements [11]. The major part of the rods was threaded to permit easy installation and variation of the gap length.