DANSK - Dansk Standard

Electrical apparatus for the detection and measurement of combustible or toxic gases or vapours or of oxygen – Requirements on the functional safety of gas detection systems
 N DS DS/EN 50402

Annotation

This European Standard is applicable to apparatus and systems for the detection and measurement of flammable or toxic gases or vapours or oxygen. This European Standard is a product standard which is based on EN 61508 (all parts) and for gas detection systems covers both low and high demand mode at SIL capabilities of 1, 2 or 3 only. Gas detection apparatus and gas detection systems are developed as generic products. This standard covers part of the phase 10 “realisation” of the overall safety lifecycle defined in Figure 2 of EN 61508-1:2010. Configuration and integration into specific applications is not covered by this standard. In the event of conflict between the requirements of this standard and those of EN 61508, EN 50402 will take precedence.

NOTE 1 – Applications requiring a SIL capability of 4 for a gas detection system are not practicable.

NOTE 2 – This European Standard is dedicated mainly to fixed apparatus. For portable gas detectors claiming a SIL higher than 1, this European Standard may be applied. This European Standard supplements the requirements of the European Standards for electrical apparatus for the detection and measurement of flammable gases, vapours (e.g. EN 60079-29-1 or EN 60079-29-4), toxic gases (e.g. EN 45544) or oxygen (e.g. EN 50104).

NOTE 3 – These European Standards are called in the text "metrological standards". The examples above show the state of the standardisation for industrial applications at the time of publishing this European Standard. There may be other metrological standards covering other application fields, for which this European Standard is also applicable. EN 50271 specifies minimum requirements for apparatus using software and/or digital components. It also defines additional optional requirements for compliance with SIL 1 in low demand mode operation. EN 50402 includes all requirements of EN 50271. EN 50402 is also dedicated to apparatus and gas detection systems and/or components and should be used in ...