Supervisory Control and Data Acquisition ( Scada ) Systems

This manual has been prepared by or for the Government and, except to the extent indicated below, is public property and not subject to copyright. Reprint or republication of this manual should include a credit substantially as Table 3-1 Safety integrity levels – low demand operation and table 3-2 Safety integrity levels – continuous operation are reprinted with permission from the International Electrotechnical Commission (IEC) publication International Standard IEC 61508-1, tables 2 and 3 from subclause 7.2.6.9. " The author thanks the IEC for permission to reproduce information from its International Standard IEC 61508-1: (1998). All such extracts are copyright of IEC, Geneva, Switzerland. All right reserved. Further information on the IEC is available from www.iec.ch. IEC has no responsibility for the placement and context in which the extracts and contents are reproduced by the author, nor is IEC in any way responsible for the other content or accuracy therein. " TM 5-601