Critical definitions you will find include:
This standard replaces the older IEC 60815 (1986) and moves away from simple look-up tables toward a more rigorous, site-specific design approach. It establishes how to determine the required to prevent insulator flashover based on environmental pollution levels. Key Content & Technical Focus iec 60815-2 pdf
The baseline creepage distance determined directly from the Site Pollution Severity (SPS) class. Critical definitions you will find include: This standard