【Safety Certification】The Clearances, Creepage Distances and Solid Insulation in Product Safety

Appliances shall be constructed so that the clearances, creepage distances and solid
insulation are adequate to withstand the electrical stresses to which the appliance is liable to be subjected.
 
Do you know the different for clearances, creepage distances and solid Insulation?
 

• Clearance

shortest distance in air between two conductive parts.
 

• Creepage Distance

shortest distance along the surface of a solid insulating material between two conductive parts.
 

• Solid Insulation

solid insulating material interposed between two conductive parts.
 
Examples of Insulation
The conductive parts A and B are mounted on solid insulating material surface.
Clearance is the "line of sight" distance. Creepage distance path follows the contour of the groove.
 
[Note] Reference Safety Standard:
- IEC/EN 60664-1
Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
 
GCS Safety Team