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Doc No. 0418D10SD01 – Rev.01 www.LiutaioCES.com

1. Functional Safety Abbreviations

%WC Percentage Weight Contribution on the Total PFDavg value

1oo1 One(1) out of One(1) safety channel architecture.

1oo1D One(1) out of One(1) safety channel architecture with Diagnostics.

1oo2 One(1) out of Two(2) safety channel architecture.

1oo2D One(1) out of Two(2) safety channel architecture with included additional Diagnostics among channels to verify safety channels interoperability.

1oo3 One(1) out of Three(3) safety channel architecture.

2oo2 Two(2) out of Two(2) safety channel architecture.

2oo3 Two(2) out of Three(3) safety architecture.

2oo3D Two(2) out of Three(3) safety channel architecture with included additional Diagnostics among channels to verify safety channels interoperability.

3oo3 Three(3) out of Three(3) safety channel architecture.

Beta (β) Common Cause Failure factor for Dangerous UnDetected failures

BetaD (β_D) Common Cause Failure factor for Dangerous detected failures

BPCS Basic Process Control System

CCF Common Cause Failure

CMF Common Mode Failure

CPU Central Processing Unit

CRV Cartridge Valve

DC (or CD_D) Diagnostic Coverage factor for Dangerous failures

DCS Distributed Control System. See "PCS".

E/E/PE Electrical, Electronic, Programmable Electronic safety-related system

ESDV Emergency Shutdown Valve

ESV Emergency Shutdown Valve

Et Proof Test Effectiveness

EUC Equipment Under Control

FE Final safety Element

FIT Failure In Time (1x10-9 per hour).

FMEA Failure Modes and Effects Analysis

FMECA Failure Modes, Effects and Criticality Analysis

FMEDA Failure Modes, Effects and Diagnostic Analysis

FSE Final Safety Element

FSM Functional Safety Management

FSP Functional Safety Plan

FVST Full Valve Stroke Test

GUI Graphic User Interface

HART Highway Addressable Remote Transducer protocol

HAZID Hazard Identification Study

HAZOP Hazard and Operability Study

HFT Hardware Fault Tolerance

HIPPS High Integrity Pression Protection System

HIPS High Integrity Protection System

HMI Human Machine Interface

HPA Hazard Process Analysis

IPF Instrumented Protective Function

IPS Instrumented Protective System

IS Intrinsically Safe

K, or Kfactor Efficiency of inter-channel comparison / automatic switch mechanism in the 1oo2D Safety Architecture. Fraction of the success of the autotest circuit in the 1oo2D system

LdDD, or l_DD Dangerous detected failure rate

LdDU, or l_DU Dangerous UnDetected failure rate

LdSD, or l_SD Safe detected failure rate

LdSU, or l_SU Safe UnDetected failure rate

MART Maximum Allowed Response Time (see “SRT”)

MRT Mean Restoration Time

MSLS Main Safety Loop Series

MSSDL Maximum SIL Safety Design Limit

MSSTRDL Maximum “Spurious Trip Rate” (STR) Safety Design Limit

MTBF Mean Time Between Failures

MTTF Mean Time To Failure

MTTF_D Mean Time To Dangerous Failure

MTTFs Mean Time To Failure Spuriously

MTTFspuriously Mean Time To Failure Spuriously

MTTR Mean Time to Restoration

N/A Not Applicable

NA Not Applicable

NDE Normally De-Energized

NE Normally Energized

NIS Non-Intrinsically Safe

OOS Out Of Service

PCS Process Control System. See "DCS".

PE Programmable Electronic

PFDavg Average Probability of Dangerous Failure on Demand

PHA Process Hazard Analysis

PRV Pressure Relief Valve

PST Process Safety Time

PTC Proof Test Coverage

PVST Partial Valve Stroke Test

QSV Quick Shutdown Valve

RBD Reliability Block Diagram

RO Restriction Orifice

RPN Risk Priority Number

RRF Risk Reduction Factor

SCA Safety Channel Architecture

SFF Safe Failure Fraction

SIF Safety Instrumented Function

SIL Safety Integrity Level

SIS Safety Instrumented System

SLf Service Life

SmPosT Smart Position Transmitter

SOV Solenoid Valve

SPST Single Pole Single Trough

SRS Safety Requirements Specification

SRT Safety Response Time

STL Spurious Trip Level

STR Spurious Trip Rate

STRavg Average Spurious Trip Rate

TBDbC To be defined by calculation case

TD Proof test Duration

TI Proof Test Period

XooN X-out-of-N voting logic, or “Safety Channel Architecture” (SCA) of N inputs/Channels where “X” inputs/Channels decide the whole SCA state.

XooN(D) Same SCA as "XooN", but additional diagnostic are included to verify safety channels interoperability.