Min. electrical clearance/ tempered component leads

In J-STD-001C, various topics says "must meet the minimum electrical clearance". I know that your company has to set those guidelines on each and every PCB but is there a generic or standard out there somewhere with tolerances?

Also, please name a few components that would be typical to having tempered leads and what exactly is the purpose...for strength and integrity. Another IPC rule-tempered leads shall not be fully clinched. Can someone make this a little clearer to me? Thanks

With low voltage carrying PCB tracks the clearance would be the practical limit of etching tolerances and the solder/ wave solder bridging tolerances.
These depend on the equipment used for this job, obviously a home etching, hand soldering board would be difficult to produce if there were two tracks in between 0.1" IC leg spacings. Yet I see that frequently on commercial boards.
For tracks carrying mains or other higher voltages there are spacing rules which google should find for you.

Can't say I have come across that tempered lead info so far. Tempering metal alters the hardness of it. Maybe the leads get more brittle by this process and are likely to break if clinched too hard?