Chrath - you should probably have put your original post either in the IEEE or NFPA forums, as I sincerely doubt that there's any townships in Indiana which have adopted IEC standards.
NEC (NFPA) does not require conduit for most installations, non-metallic jacketed cable (such as Romex) or metallic/armoured cable (such as type AC, BX) is often sufficient. However, as mentioned by resqcapt19, there are MANY jurisdictions, especially in or near to urban areas, which reject Romex/AC/BX/etc., and instead required EMT.
You should check with your local AHJ.