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Chemical Technology • March 2015
functional safety requirements, as is the case for the use
of fixed barriers to permanently prevent access or to retain
hazards. Permanent separation of individuals from hazards
is clearly a safety function, as is evident by the number of
machines on the market with permanently fixed guards or
shields in place. While these components of the overall safety
system have specific requirements pertaining to proper de-
sign and use, these elements do not have functional safety
CONTROL &
INSTRUMENTATION
Figure 2: Visual representation
Figure 1: Application of protective measures