A CRN is a number issued by each province or territory of Canada to the design of a boiler, pressure vessel or fitting. The CRN identifies the design has been accepted and registered for use in Canada. A hospital or business that have equipment being used in Canada without a CRN are held liable, their insurance is void, and if caught before any damages occur, the equipment must be removed from the hospital or premises immediately. It is not illegal to “sell” equipment without a CRN, but it is illegal to operate that equipment in Canada. ON2 GUARANTEES that ALL PRESURE VESSELS used with our Oxygen Concentrator Systems have CRN numbers and are registered for use in their province, territory, and Canada!