in the PCB I am designing there is 0.88mm between one track and a through hole pad. Between the track and the pad there is a DC voltage difference of around 425V.
Clearance calculators like this one specify a minimum clearance of 0.8mm for 500V if "external conductors coated" are used. If that is the case, I am safe, but I am not sure about what "external conductors coated" refers to.
The track and the pad are in the top layer, so I assume they are external, but are they coated? that coating is referred to a standard solder mask or is it a special one?
If the clearance is not enough I have two options: 1. Apply a coating after soldering. (I am not sure how yet) 2. Cut the problematic track and use a wire instead
What do you think it is best? this is the problematic track: