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CYBerseCurItY For InDustrIAL ControL sYsteMs
Safety Integrity Levels and Security Assurance Levels
During the 1990s a rising number of industrial incidents catalyzed
a detailed review of industry safety practices and a push toward stan-
dardized levels of practice. is resulted in the Industrial Society of
Automation (ISA) creating ANSI/ISA-84.00.01-1996, which denes
the safety integrity levels for use in assessing safety requirements for ICS
components and safety systems. e standard focuses on risk reduction
through a systematic process associated with hardware faults and failures.
A safety integrity level (SIL) is a probability of mec ...