(a) Any boiler or pressure vessel having been inspected and declared unfit for further service by an Inspector shall be stamped by the Chief Boiler Inspector or a Deputy Inspector on either side of the state number with the letters "XXX" as shown by the following facsimile which will designate a condemned boiler or pressure vessel:XXXOOOOOXXX
(b) Any person, firm, partnership, or corporation using or offering for sale or rent a condemned boiler or pressure vessel for operation within this State shall be subject to the penalties provided by the Act.