SI057002_MNL - Gasoline Overfill Protection SIS IMMEAS-SIS1 Management Manual

Immingham Storage Co Ltd - East Terminal

Gasoline Storage Tanks Overfill Safety Instrument System - Functional Safety Assessment Stage 2/3

P & I Design Ltd

DOCUMENT NO: SI277016_RPT

2 Reed Street, Thornaby, UK, TS17 7AF

ISSUE: D DATE: 25.04.13

Tel: + 44 (0)1642 617444

PAGE 15 OF 33

Fax: + 44 (0)1642 616447

There is no requirement for any software as the logic solver consists of individual solid state

relay logic.

The valves are dedicated as an import valves; therefore there is no requirement to override the

SIFs.

The system is designed to fail safe on any fault being detected in the SIS. No reset would be

available.

Mean time to repair shall be 72 hours or less. Immingham Storage Company East to approve

following consideration of availability of spares and labour.

There are no conceivable individually safe process states which, when occurring concurrently,

can create a separate hazard.

Referenced in SRS:

This system will be installed in mainland UK where it will not be subjected to extremes of

temperature or humidity. We do not consider that

grounding, electromagnetic

interference/radiofrequency interference (EMI/RFI), shock, vibration, electrostatic discharge,

flooding or lightning

will have a detrimental effect on the SIS. The system is designed to fail

safe on any loss of electrical power. The individual elements of the system shall be designed

for the process and operating conditions, the environment and the site electrical area

classification. Specifically, all wetted parts should be suitable for Petroleum Spirit.