This part of IEC61326 covers all equipment within the scope of IEC61326‑1 , but is limited to systems and equipment for industrial applications intended to perform safety functions as defined in IEC61508 with SIL 1-3. The electromagnetic environments encompassed by this product family standard are industrial, both indoor and outdoor, as described for industrial locations in IEC61000‑6‑2 or defined in 3.8 of IEC61326‑1 . Equipment and systems intended for use in other electromagnetic environments, for example, in the process industry or in environments with potentially explosive atmospheres, are excluded from the scope of this document. Equipment and systems considered as “proven-in-use?? according to IEC61508 or “prior use?? according to IEC61511 are excluded from the scope of this document. Fire alarm systems and security alarm systems intended for protection of buildings are excluded from the scope of this document.