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Local Fuel plc – Shoreham Oil Terminal
Safety Instrumented Systems – Policy and Lifecycle Activities
P & I Design Ltd
DOCUMENT NO: LF364003_RPT
2 Reed Street, Thornaby, UK, TS17 7AF
ISSUE: C DATE: 12.06.15
Tel: 00 44 (0)1642 617444
PAGE 8 OF 19
Fax: 00 44 (0)1642 616447
www.pidesign.co.uk5.5
Safety Requirement Specification
Local Fuel plc will produce or have produced for them a Safety Requirement Specification,
the purpose of which is to:
Define Safety Instrumented Functions and Safety Integrity Levels.
Provide information to fully define the intended SIS, by defining:
o
The Process and the Process Safe State.
o
System Architecture.
o
Time of response.
o
The demand on the System.
o
Settings, Calibrated Ranges and Levels of Concerns.
o
Process and Environmental Limitations.
o
Interface with other control systems and protection layers.
o
Manual Shutdown methods.
o
Override facilities if required. (Overrides are avoided unless absolutely
necessary).
o
Spurious Trip acceptability.
o
Proof Test Requirements.
Provide the System Integrator and or suppliers the Basis of Design for development
of the SIS.
As shown in Figure 1, verification of the Safety Requirement Specification is required at this
lifecycle phase. The Functional Safety Manager is responsible to ensure that this verification
is completed as defined in the Safety Plan. Local Fuel plc have developed checklists to record
the verification process.
The Safety Plan will have identified if a Functional Safety Assessment (FSA) Stage 1 is to be
performed. If it is required then the Functional Safety Manager will arrange for an assessment
to be conducted.
A full list of requirements to be detailed within the SRS can be found in BS EN 61511 - 2004 Clause 10.3