Pull apart the average computer dialup modem (what are they???) or an old fax machine and see what they do for circuit protection. You'll find most of that stuff in there. If you're going to design a product for any market, it pays to get the appropriate standards. Just because the app not for the chip you're using makes some recommendations that does not make your product compliant necessarily. By reviewing the relevant standards at least you're armed with the full picture.

most of my work is standards based these days - IPC standards for pcb design and manufacture, AS, IEC,UL and EN standards for EMC and safety. MISRA for 'c' coding guidelines. It makes for interesting bedtime reading!