(a) Secondhand boilers, when of the stationary type and used for stationary purposes only, shall be deemed secondhand only when both ownership and location are changed, and shall have a factor of safety of at least 5.5 when of buttstrap construction and a factor of safety of not less than six where of lap seam construction. These factors shall be increased by the inspector as the condition and safety of the boiler demand, and in no case shall the factor of safety be less than provided for in sections 14-10.1 to 14-10.4 of this Subpart, inclusive, unless constructed in accordance with the rules in Subpart 14-9 of this Part when the factor of safety shall be not less than the requirements of section 14-1.4 of this Part.

(b) Portable boilers, such as used by contractors, agriculturists, sawmills, etc., used for purely portable purposes and transported from place to place, shall be deemed secondhand in the event of change of ownership, irrespective of change of location, and shall have a factor of safety of at least 5.5 where of buttstrap construction and a factor of safety of not less than six where of lap seam construction.