The indoor wiring of electrostatic grounding and equipment grounding should be firm and practical. For factory buildings with larger space, it can be arranged in a nine-square grid above the lines in use. For medium-sized spaces, it can be arranged in a "well" shape, or it can be arranged above the lines in use along the existing bridge lines. For smaller spaces, laboratories, and office buildings, the layout can be combined with ceiling and ground wiring. The secondary main line should be horizontal and vertical, and should be as firm, practical, concealed, and beautiful as possible.