Rockwell Automation 8000 Series TMR System - Manual (Page 17)

OPERATOR AND MAINTENANCE MANUAL
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2. OPERATION
A safety Instrumented system (SIS) is dormant by nature, therefore in normal plant
operating situations the SIS is not required and is only called upon to operate in an
emergency situation.
A SIS should be designed to operate automatically and so requires no operator
interaction. It is essential however that the SIS and associated field devices are
maintained, to ensure they operate when required.
Before accepting ownership of a system an operator should be satisfied that the
SIS has been installed and commissioned to the latest approved design documents
and signed off by certifying authorities (where applicable). It is essential that
document masters are maintained and fully traceable.
Modifications should not be carried out without a safety assessment and relevant
approval. Modifications to a SIS, including the application, field devices and
hardware, may impact the reliability and availability of the system.
Operators should know which SIS diagnostic and operational alarms are
annunciated, and where they appear. For example, a system may be configured to
annunciate a common status diagnostic alarm to an operator interface
(SCADA/DCS etc) that requires further investigation at the panel, while all
operational alarms may be individually reported on a first up basis.
Operators should be familiar with the location of the SIS documentation, spares
and contact details for technical support.