Indiana statute (IC 22-15-6) and administrative rules (680 IAC 2) do not require licensing of boiler operators.
Note 1: A voluntary licensing program is available through the Indiana Association of the National Association of Power Engineers (NAPE). NAPE has several chapters of their association representing various regions in Indiana.
Note 2: The federal Environmental Protection Agency have promulgated requirements for licensing of employees operating large power production boilers owned by electric utilities. http://www.in.gov/legislative/iac/iac_title?iact=680&iaca=2