In addition to those requirements listed in WAC 296-104-301 and 296-104-302, the following are required with regard to installations or refits of gas, oil, or combinations of gas or oil:

(1) All boilers installed or refitted after December 1998, shall be equipped with suitable primary (flame safeguards) safety controls, safety limit switches, and burners or electrical elements as required by a nationally or internationally recognized standard.

(2) The symbol of the certifying organization that has investigated such equipment as having complied with nationally or internationally recognized standard shall be affixed to the equipment and shall be considered evidence that the unit was manufactured in accordance with that standard. A certifying organization is one that provides uniform testing, examination, and listing procedures under established, nationally or internationally recognized standards, and that is acceptable to the authorities having jurisdiction.

(3) These devices shall be installed in accordance with jurisdictional requirements, manufacturer's recommendations, and/or industry standards as applicable.