Anyone help me to understand on what basis TVS Dide D8 and D10 are selected. It is an automotive application.

I assume, D8 is used for protection against ESD. But I don't have any idea on selection criteria. This circuit is intended to work between 9–32VDC but used ESD diode is way higher rated, also in series they are using D10 which is in Forward biased condition. Why it is used in FB?

 

What sort of diodes ARE THOSE?? I have not looked up the numbers yet, the TS should do that. Protecting against transients in both directions is a good guess. What sort of electronic device in what sort of automotive application is this for. That matters.