Functional Safety Engineering/SIL (Safety Integrity Level) studies are implemented throughout the entire lifecycle of the Oil & Gas facilities i.e. during the engineering design phases (FEED & Detailed Design), construction, commissioning and the operation of these facilities.

The relevant studies are as follows:

1. SIL Assessment & Classification

This study is to determine the SIL level/target of the SIF (Safety Instrumented Function)/IPF (Instrumented Protective Function) of the facilities and it is carried out accordance to :

• IEC 61508/61511
• PTS 32.80.10.10 (PETRONAS Technical Standards)
• DEP 32.80.10.10 (SHELL Design & Engineering Practice)

2. SIL Verification & Implementation

AZSB utilises EXIDA’s exSILentia verification tools and failure rates data (PFDavg) to perform SIL Verification & Implementation calculations.

3. Safety Requirements Specifications (SRS)

This scope requires AZSB to develop the SRS, documenting the technical specifications and requirements of ALL components of the SIF/IPF loops such as the initiator, IS barrier, input modules, logic solver, output modules, actuator, solenoid and shutdown valves; as per the SIL Classification exercise.

The SRS is a lifecycle document, which will be updated at the different phases of the facilities such as the SIL Verification exercise (detailed design phase), construction & commissioning phases and Operation & Maintenance phaseof the facilities.