63 / 81
Local Fuel plc - Shoreham Oil Terminal
Safety Instrument System Functional Safety Assessment Stage 5
P & I Design Ltd
DOCUMENT NO: LF364100_RPT
2 Reed Street, Thornaby, UK, TS17 7AF
ISSUE: A DATE: 15.06.2015
Tel: + 44 (0)1642 617444
PAGE 14 OF 32
Fax: + 44 (0)1642 616447
www.pidesign.co.uk5
REVIEW OF REVISED LIFECYCLE DOCUMENTATION
5.1 Layer of Protection Analysis
The LOPA has been reviewed and accepted by the HSE. The SIL 2 Overfill Protection System
within the LOPA was estimated with a PFD of 0.005.
5.2 Safety Requirement Specification
Although this FSA is a Stage 5, it was decided to fully review all documentation, not just that
required as part of the modification. This was decided upon as all documentation has been re-
issued for Local Fuel plc and is effectively new issues.
In order to ensure compliance to BS EN 61511 the SRS was reviewed as follows:
5.2.1
Do the Safety Instrumented Functions (SIF) derive from a HAZOP or LOPA study, if not where
are they derived from. BS EN Clause 8 & 9.
Section 2.1 of the SRS references the LOPA and the requirements for a SIL 2 SIS to be
installed on the gasoline tanks.
5.2.2
Has the Safety Integrity Level (SIL) for each SIF been allocated. BS EN Clause 9.
Section 4.6 of the SRS details the SIF requirements for Tanks 1, 2, 3 & 4, which prior to the
proposed Marine Gas Oil modification were all available for gasoline. As stated previously
the LOPA considered that only two of these tanks would be utilised.
ACTION 1:
5.2.3
Has the demand on the SIF been specified (demand or continuous). BS EN Clause 10.
Section 3 of the SRS confirms that the system is a low demand SIS with a demand on the SIF
of no more frequently that one in every ten years.