Here are some of the more popular EMI Requirements specifications :
Military :
* MIL-STD-461 (latest includes 462 and 463)
* MIL-STD-464
Aviation :
* DO-160
Medical :
* IEC 60601-1-2
Marine :
* NMEA 2000
Consumer / Industrial :
* FCC part 15 Class B & Class A
know of any others ?