Fire & Gas Detection System
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REVISION INDEX SHEET
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Fire & Gas Detection System
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1. General
This specification describes the modifications to the Project Specification, A3CA-06011-FP-002, Specification for Fire & Gas Detection System, for the PTTLNG Jetty Development and LNG Receiving Terminal Project to be built at Map Ta Phut industrial estate, Rayong, Thailand.
Instruction contained in this specification such as "Add", "Modify" and "Delete" shall be interpreted as follows:
Add : The requirement shall be read as a continuation of the Project Specification.
Modify : The requirement in the Project Specification shall be replaced by the requirement in
this specification.
Delete : The requirement in the Project Specification is no longer effective.
2. Modifications to Project Specification A3CA-06011-FP-002
2.1 Article 1.1 General(Modify)
The Vendor shall have full responsibility for furnishing a complete and workable system including all equipment and services to meet the functional requirements and the reference project specifications, codes and standards specified herein.
(Modify)
Compliance by the Vendor with the requirements of this specification does not relieve the
Vendor of his responsibility of supply equipment, which is of proper design and construction,
fully suited for all specified conditions.
2.2 Article 1.3 System Overview
(Modify)
All Buildings FGS systems shall be designed per NFPA 72 as well as all applicable Building Codes. Vendor to confirm during detailed design. Vendor’s design shall require PTTLNG/PMC agreement and approval before proceeding.
(Modify)
The FGS is one of the instrument systems which form part of the overall Integrated Control System (ICS). Testing of all interfaces between FGS and other parts of ICS is detailed in specification 7S92-06011-CS-TS-003 "Specification for Process Control System ". This specification defines also the boundary for the FAT and SIT.
Fire & Gas Detection System
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2.3 Article 2.1 Project Specifications and Drawings
(Modify)
7S92-06011-CS-TS-001 Instrument Design Criteria
7S92-06011-CS-TS-007 Specification for Control Panels
7S92-06011-CS-TS-002 Integrated Control and Safety
System Philosophy
7S92-06011-CS-TS-003 Specification for Process Control
System
7S92-06011-CS-TS-004 Specification for Safety Instrumented
Systems
7S92-06011-FP-TS-002 Fire Protection Philosophy ( Design
Criteria)
7S92-06011-0300-EL-001 Area Classification Drawings, Electrical
2.4 Article 3.0 Abbreviations
(Modify)
FIT Factory Integration Test (carried out by PCSI (Vendor))
2.5 Article 4.1 Equipment Location
(Modify)
The system shall be installed in air conditioned buildings where the climatic conditions shall be as prescribed in 7S92-06011-CS-TS-001, Instrument Design Criteria.
2.6 Article 5.1 Equipment Location and Design Criteria
(Modify)
The AIR will have HVAC equipment to maintain environmental conditions. The Vendor shall confirm whether special conditions are required.
2.7 Article 5.3.1 Power Supplies
(Modify)
a) Power supplies shall be provided in accordance with specification
Fire & Gas Detection System
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(Modify)
b) FGS cabinets shall be fed from redundant 230 VAC – UPS instrument distribution boards.
2.8 Article 5.3 Earthing System
(Modify)
5.3.2 For cabling and Earthing concepts, refer to 7S92-06011-CS-TS-001 “Instrument Design Criteria”.
2.9 Article 5.6 Time Synchronization
(Modify)
The FGS shall be synchronized with the plant master clock system (GPS).
2.10 Article 5.7 FGS Graphics Specification
(Modify)
The FGS graphic specification shall be developed by Vendor during detailed design and shall follow the PCS graphic specification.
2.11 Article 6.4 System Cabinets
(Modify)
6.4.6 FGS cabinets shall comply with 7S92-06011-CS-TS-007 “Specification for Control Panels”.
2.12 Article 6.8 Cabinet Mounted Panels
(Modify)
Vendor shall ensure that all cabinet mounted panels are equipped with a common lamp
test pushbutton.
2.13 Article 6.10 Local Fire & Gas Control Panel
(Modify)
The LFGCP shall be capable of controlling all alarm functions for buildings that being
1
Fire & Gas Detection System
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controlled.
2.14 Article 7.1 General
(Modify)
FGS Cause and Effect Diagrams (By CONTRACTOR) : 7S92-06011-PC-DS-205 Piping and Instrument Diagrams (P&ID) for Fire Fighting :
7S92-06011-1000-FP-001~012/ 301~304
Fire and Gas Plan Drawings : 7S92-06011-1300-CS-360
SHE requirements in the Project Specification, Annex J, section 12.
2.15 Article 7.3 CCR FGS Control Panels
(Modify)
7.3.1 A FGS 52” touch screen LCD monitor Mimic Panel shall also be provided in the Fire Station Building, this facility will be for "Read Only" purposes.
2.16 Article 8.1 General
(Modify)
The provisional quantities and location of detectors are shown on Fire and Gas Detection Plan drawings 7S92-A1-06011-1300-CS-360.
2.17 Article 8.4 Smoke Detectors
(Modify)
8.4.2 Smoke detectors shall be either fixed head or reflection type. Smoke detectors shall not be provided for indoor cable trays. The Vendor shall ensure optimum operation of the detector system.
2.18 Article 9.1 General
(Modify)
This section describes equipment which is activated by the FGS.
The Vendor shall ensure that all interfaces between the FGS and following equipment are correctly engineered.
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2.19 Article 11.5 Consumables and Spare Parts
(Modify)
The Vendor shall provide up to the completion of commissioning all consumable items as defined in the project specification.
2.20 Article 11.6 Documentation
(Modify)
The Vendor shall include in his tender any restriction relating to the application of this system for the specific TUV Class requirement.
2.21 Article 13.1 General Requirements
(Modify)
Vendor shall be responsible for ensuring directly or indirectly that a fully integrated test of the
FGS is performed. This test shall simultaneously incorporate every different component (s) to prove functionality and reliability, simulating site logistics and environmental conditions where possible.
2.22 Article 13.3 System Staging
(Modify)
Vendor shall maintain a detailed logbook covering the following areas:
- Material deficiencies - System activity
- System problems and resolutions - System testing
(Modify)
Load taking devices shall be simulated at the input /output terminals.
The Vendor is to advise the environmental conditions under which the burn-in takes place (i.e. ambient temperature and humidity).
2.23 Article 14.0 FGS Block Diagram
(Add)
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Fire & Gas Detection System (FGS)
3. Attachment
7S92-A3-06011-1300-CS-023, Rev. 0, System Block Diagram for Fire & Gas Detection System (FGS)
PTTLNG Company Limited
Jetty Development and LNG Receiving Terminal Project
Front End Engineering Design
Specification
for
Fire & Gas Detection System
Document Number: A3CA-06011-FP-002
4 9 Jul 07 Issued to EPC
Contractor
VM GH GH
Rev Date Description By Checked Approved Acknw’ed by
Table of Contents
Page1.0 SCOPE... 1
1.1 General...1 1.2 Objectives...2 1.3 System Overview...22.0 CODES AND STANDARDS ... 3
2.1 Project Specifications and Drawings ...3
2.2 Local Codes and Standards...4
2.3 International Standards...4
3.0 ABBREVIATIONS... 4
4.0 CLIMATIC AND SITE DATA ... 5
4.1 Equipment location ...5
4.2 Area Classification ...5
5.0 GENERAL REQUIREMENTS ... 5
5.1 Equipment Locations and Design Criteria ...5
5.2 Reliability and Redundancy...6
5.3 Electrical Requirements ...6
5.4 System Spareage and Loading Criteria...7
5.5 Standard Hardware and Software ...7
5.6 Time Synchronization ...7
5.7 FGS Graphics Specification ...7
6.0 HARDWARE REQUIREMENTS ... 8
6.1 General...8
6.2 Main Fire and Gas Control Panel ...8
6.3 SER Hardware...9
6.4 PLC System...10
6.5 Engineering Workstation ...11
6.6 MIMIC Panel...11
6.7 Main Distribution Frame (MDF) Cabinets ...11
6.8 Cabinet Mounted Panels...12
6.9 Input / Outputs Structure ...12
6.10 Local Fire & Gas Control Panel...15
6.11 Earth Leakage Detection...16
6.12 System Segregation...17
7.0 FUNCTIONAL REQUIREMENTS ... 17
7.1 General...17
ii
7.3 Human Machine Interface (HMI) ...19
7.4 Serial Communications ...21
7.5 Interfaces with Other ICS Systems ...21
7.6 Compliance...22
7.7 Diagnostics ...23
8.0 DETECTION SYSTEMS ... 23
8.1 General...23
8.2 Flammable Gas Detection...23
8.3 Fire Detection ...25
8.4 Buildings ...26
8.5 LNG Leakage Detection...27
8.6 Toxic Gas Detection...28
8.7 Detectors Voting ...28
9.0 ACTIVATION SYSTEMS ... 28
9.1 General...28
9.2 Water Spray / Deluge / Foam Systems ...28
9.3 Audible Alarm and Beacon Systems ...29
10.0 CONFIGURATION AND PROGRAMMING EQUIPMENT ... 30
10.1 General...30
10.2 Editing...30
10.3 Configuration ...31
11.0 PROJECT REQUIREMENTS ... 31
11.1 FGS Scope of supply and Services...31
11.2 Project Execution...31
11.3 Standardization...31
11.4 Description and System Sizing Data ...32
11.5 Consumables and Spare Parts ...32
11.6 Documentation...32
11.7 Software and Software Documentation ...32
12.0 ENGINEERING AND TRAINING SERVICES ... 33
13.0 INSPECTION AND TESTING ... 33
13.1 General Requirements...33
13.2 Manufacturing Test ...33
13.3 System Staging...34
13.4 Factory Acceptance Test (F.A.T.) ...34
13.5 System Integration Testing (SIT)...36
13.6 Site Acceptance Test ...36
1.0
SCOPE
1.1 General
This specification defines the minimum technical requirements for the design, materials, fabrication, assembly, inspection, testing, and performance, of a complete fire and gas detection system for the PTT LNG Receiving Terminal Project (hereafter described as the TERMINAL). The Fire & Gas Control System (FGS) shall include all necessary appurtenances, accessories, auxiliaries and controls as required for a fully operable integrated system.
The technical design, hardware, configuration and functionality of the FGS shall generally comply with the following:
NFPA 72 - “National Fire Alarm Code” and NFPA 59A - “Standard for the Production, Storage, and Handling of Liquefied Natural Gas (LNG).
Human Machine Interface (graphical presentation) will be carried out via the Mimic panel in the main control room, VDU operator console, the PCS and in combination with hardwired switch panels.
The Contractor shall have full responsibility for furnishing a complete and workable system including all equipment and services to meet the functional requirements and the reference project specifications, codes and standards specified herein.
The fire & gas detection system shall be capable of interfacing to other systems via both hard-wired and soft links, as described below. For the critical signals, the interfacing utilized will be hard-wired, but for the alarm, status, and non-critical signals, the interfacing utilized will be soft-link.
Emergency Shutdown System (ESD) Process Control System (PCS) HVAC System
PA/GA System
Fire Protection System (e.g. Water Spray or Foam Systems)
Compliance by the CONTRACTOR with the requirements of this specification does not relieve the CONTRACTOR of his responsibility of supply equipment, which is of proper design and construction, fully suited for all specified conditions.
1.1.1 The FGS shall as a minimum contain: - *Fire Sirens and Horns
- *Detectors
*Programmable Logic Controller
- *Isolators and field termination (housed in MDF cabinets) - *System Cabinets and Cables
- *HMI Displays
- *Switch Panels (for control panels mounting) - *Cabinet mounted Engineering workstation - *A SER system including:
-Printer
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- Main Fire and Gas Control Panel (MFGCP) – PLC Based Architecture - Local Fire and Gas Control Panel (LFGCP) – Addressable,
Microprocessor Based
The Building FGS system shall be a complete addressable fire and gas detection System.
1.1.2 FGS equipment for the Jetty Area and Truck Loading shall be integrated with the main FGS via remote I/O.
1.1.3 Deleted
1.2 Objectives
1.2.1 The principal objectives of the Fire and Gas System (FGS) are:- The protection of personnel.
The protection of environment.
The protection of equipment, plant and structures. 1.2.2 The FGS shall achieve these objectives by:-
- Detecting, at an early stage, the presence of flammable and toxic gases. - Detecting incipient fire and the presence of fire.
- Providing automatic and / or facilities for manual activation of the fire protection system, as required.
- Initiating signals, both audible and visible, as required, warning of the detected hazards.
- Provide sequence of event recording for analysis purposes
1.3 System Overview
All Fire and Gas safety critical functions shall be implemented with independent instrumentation and shall be hardwired to the FGS system logic. FGS sensor signal processing and system logic (PLC's) shall be geographically distributed as individual FGS sub-systems in various process and utility plant located Field Auxiliary Rooms (FAR's), Auxiliary Instrument Rooms (AIR’s) and the CCR.
Dedicated F&G control panels shall be provided in the CCR, which will comprise of VDU's and a hard wired switch panel. The control panels shall be integrated with the Mimic panel.
The VDU's will graphically display the geography of the site, presenting alarm conditions via a variety of hierarchical screens (e.g. total overviews and specific zoned locations). The control cabinets shall also provided with hard wired switches to initiate FGS protection and alarm systems where appropriate.
The control and monitoring system for the FGS shall be PLC based. It shall form the basis of each sub-system and shall communicate with:
the CCR FGS control panels (VDU / printer) for display, recording and transmission of receipt of the status of fire and gas devices.
the CCR FGS mimic panel for display of the status of fire and gas devices throughout the TERMINAL.
the CCR FGS control panels (hard wired switches) for safety critical functions.
other sub-system FGS PLC's for the initiation of alarm and protection systems etc.
All Buildings FGS systems shall be designed per NFPA 72 as well as all applicable Building Codes. CONTRACTOR to confirm during detailed design. CONTRACTOR’s design shall require PTTLNG/PMC agreement and approval before proceeding.
For main alarm overview and hardware layouts, the LNG complex shall be split into geographical areas. These shall be:
The process and utilities areas
The Truck Loading area
The Jetty Unloading area Berth #1 The Jetty Loading area Berth #3
The building areas
All Instrumented Protective Function (IPF) initiators shall have independent instrumentation and shall be hardwired to the FGS system logic.
The FGS is one of the instrument systems which form part of the overall Integrated Control System (ICS). Testing of all interfaces between FGS and other parts of ICS is detailed in specification A3CA-06011-270-70005 "Specification for Process Control System ". This specification defines also the boundary for the FAT and SIT.
2.0
CODES AND STANDARDS
The equipment shall comply with the latest issue of the following documents:-
2.1 Project Specifications and Drawings
A3CA-06011-270-70001 Instrument Design Criteria
A3CA-06011-270-70003 Specification for Control Panels
A3CA-06011-270-70004 Process Control and Safety
Instrumented Systems Philosophy
A3CA-06011-270-70005 Specification for Process Control
System
A3CA-06011-270-70006 Specification for Safety Instrumented
Systems
A3CA-06011-1000-FPR-001 Fire Protection Philosophy ( Design
Criteria)
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2.2 Local Codes and Standards
Applicable Thai Codes and Standards
2.3 International Standards
National Fire Protection Agency (NFPA)
NFPA 59A (2006): Standard for the Production, Storage, and Handling of Liquefied Natural Gas (LNG)
NFPA 70: National Electric Codes
NFPA 72: National Fire Alarm Code
NFPA 496: Purged Enclosures for Electrical Equipment
International Electrotechnical Commission (IEC)
IEC 60529: Degrees for Protection Provided by Enclosures (IP Code)
British Standards Institution
EN 1473(1997): Installation and Equipment for Liquefied Natural Gas – Design of Onshore Installations
BS 5445 Specification of components of automatic fire detection systems (Parts 1 - 2 - 7 - 8).
BS 5839 Fire Detection and Alarm Systems in Buildings
BS 6020 Instrumentation for the detection of combustible gases.
3.0
ABBREVIATIONS
AIR Auxiliary Instrument Room
CCR Central Control Room
CCTV Closed Circuit Television
CPU Central Processing Unit
DCS Distributed Control System
EDP Emergency Depressurizing
EPCC Engineering Procurement Construction Commissioning Contractor
EMC Electro Magnetic Compatibility
ESD Emergency Shutdown
FAT Factory Acceptance Test
FAR Field Auxiliary Room
FIT Factory Integration Test (carried out by PCSI) FGCP Fire and Gas Control Panel
FGS Fire and Gas System
HMI Human Machine Interface
ICS Integrated Control and Safety System
IPF Instrumented Protective Function
IPS Instrumented Protective System
I/O Input/Output
IS Intrinsically Safe
LAN Local Area Network
LEL Lower Explosive Limit
MCP Manual Call Point
MCR Main Control Room
MDF Main Distributed Frame
MOS Maintenance Override Switch
MOES Maintenance Override Enable Switch
NFPA National Fire Protection Association
PCS Process Control System
PCSI Process Control System Integrator
PLC Programmable Logic Controller
RDAS Rotating Equipment Data Acquisition System
SAT Site Acceptance Test
SER Sequence of Events Recorder
SIS Safety Instrumented System
SIT System Integration Test (carried out by PCSI)
SIGTTO Society of International Gas Tanker and Terminal Operators
SOV Solenoid Operated Valve
TCS Terminal Control System
TSO Tight Shut Off
UPS Un-Interruptible Power Supply
VDU Visual Display Unit
4.0
CLIMATIC AND SITE DATA
4.1 Equipment location
The system shall be installed in air conditioned buildings where the climatic conditions shall be as prescribed in A3CA-06011-270-70001.
It is a requirement that the systems shall be capable of operating for prolonged periods at temperatures up to 40 °C.
4.2 Area Classification
All instrumentation shall be designed and installed in compliance with area classification. For reference see area electrical classification drawing.
5.0
GENERAL REQUIREMENTS
5.1 Equipment Locations and Design Criteria
FGS electronic hardware which is connected to the process plant located equipment shall be housed in non-hazardous Auxiliary Equipment Rooms (AIR), FAR or CCR.
The AIR will have HVAC equipment to maintain environmental conditions. The Contractor shall confirm whether special conditions are required.
AIRs will be employed to house the majority of the Integrated Control and Safety System (ICS) hardware, which will be interconnected to the CCR and remote control rooms by fiber optic cable.
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The following locations will contain AIRs for the installation of FGS equipment PLC cabinets:
- Jetty Substation - Truck Loading CR - CCR – AIR
5.2 Reliability and Redundancy
5.2.1 Reliability
FGS are required to have high availability, reliability and integrity. A system reliability analysis shall be provided for the systems part of scope.
The analysis shall include Mean Time Between Failure figures and availability values of every module employed in the system.
- Mean Time Between Failures (MTBF) - > 80,000 hours - Mean Time to Repair 4 hrs. (Max)
- Availability - > 99.99 % 5.2.2 Redundancy
FGS shall be designed to avoid unexpected failures of software and or hardware and provide a level of high availability. These requirements lead to redundancy of system hardware. Details for PLCs are described in paragraph 6.0.
5.3 Electrical Requirements 5.3.1 Power Supplies
c) Power supplies shall be provided in accordance with specification A3CA-06011-270-70006 and
d) FGS cabinets shall be fed from dual 230 VAC – UPS instrument distribution boards.
e) Separate sets of redundant power supplies are required for: - System related hardware
- Field related hardware
f) Status indication and fault alarm of all power supply modules inside the cabinets shall be provided.
5.3.2 Earthing System
For cabling and Earthing concepts refer to A3CA-06011-270-70001 “Instrument Design Criteria”.
5.3.3 The Contractor shall ensure that the earthing is in full compliance with the ICS Vendor specific earthing requirements.
5.4 System Spareage and Loading Criteria
5.4.1 Spareage Requirements
Spare = Installed I/O - Used I/O * 100 %
Used I/O
Spare hardware and space shall be included as follows:-
a) Minimum 20 % fully connected and functional spare I/O shall be available following plant commissioning. This spareage shall be evenly distributed throughout the system.
b) Multi-pair cables terminating in MDF cabinets shall include at least 20 % unused pairs which shall be connected in sequence to spare terminals along with used pairs. The Multipair spares shall be available post plant commissioning
c) Additionally, systems shall include wired rack / slots to enable system I/O to be increased by 20 % after plant commissioning (cards shall not be installed). It shall be possible to add such hardware without shutting down the system and without causing process upset.
5.4.2 Loading Criteria
a) After plant commissioning, microprocessor based system capacity, RAM and communications bus loading shall not exceed 70 %, of the maximum capability.
b) Power supply units shall be sized such that they are only loaded to 50 % of their capacity (inclusive projected expansion).
5.5 Standard Hardware and Software
FGS systems shall employ standard hardware and software of the Vendor's own design and supply.
Vendor supplied hardware and software shall be TUV approved.
5.6 Time Synchronization
The FGS shall be synchronized with the plant master clock system. Subsystem clocks shall be synchronized at a suitable frequency to ensure that the SER resolution time stamping is not compromised. The necessary interfaces to the master clock system shall be provided.
5.7 FGS Graphics Specification
The FGS graphic specification shall be developed by CONTRACTOR during detailed design and shall follow the PCS graphic specification. The number of pages should cover the whole plant area (ie. example, process, utilities, building, truck loading, jetty area, etc). Moreover, PTTLNG/PMC shall agree and approve before proceeding.
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6.0
HARDWARE REQUIREMENTS
6.1 General
The fire and gas detection system for the TERMINAL shall consist of a PLC based system for the Process Units with an integrated MFGCP consisting of graphics display, networking communication system. Each building or occupied shelter shall include a dedicated addressable microprocessor based LFGCP complete with local audible notification system. The MFGCP shall communicate with the plant emergency evacuation notification system via the PAGA system.
Activation of critical functions between systems (i.e. HVAC, Fire Protection Equipment, etc) shall be via hard wired I/O from the MFGCP System.
Trip signals from any LFGCP shall be hard wired to the MFGCP for processing and trip activations. No trip signals to critical systems shall be allowed directly from the LFGC P.
The FGS shall be based on PLC technology and carry TUV approval.
The overall FGS shall comprise of individual stand alone sub-systems, located in equipment rooms, which are connected to FGS equipment in the main control building AIR.
Each FGS sub-system shall communicate via serial communication by means of a dedicated fail safe, self checking and fully redundant bus system.
The FGS equipment shall monitor its own hardware and all field circuits which are not “self revealing" (normally de-energized) and the system shall annunciate unrevealed signals to PCS.
The system shall as a minimum annunciate all faults at PLC card level.
All FGS detectors shall be individually connected to the FGS logic system and shall operate with either analog 4-20 mA inputs or digital volt free contact inputs, which shall facilitate individual monitoring of FGS detectors i.e. continuous line monitoring. Where required interface modules shall be used between field instrumentation and PLC I/O (e.g. Isolation barriers and signal conditioning units).
6.2 Main Fire and Gas Control Panel
MFGCP located in the CCR, shall include a networked command center with a graphics display for communicating to the facility operator status of all the fire and gas detection devices and fire protection system inputs for the TERMINAL. The panel shall monitor the fire, gas, LNG leak, and trouble alarms from individual building LFGCPs and display the information on its LCD screen.
In addition to the control and monitoring capabilities, MFGCP shall also function as a data acquisitioner and communicate all its pertinent data to PCS via a data link (e.g. Modbus protocol via RS485). The collected data will then be configured and displayed (by others) on the dedicated F&G screen among the workstations located in the CCR. The MFGCP shall be supervised around the clock. A permanent record of all alarms received shall be maintained at the MFGCP and in the PCS Historian database. The MFGCP shall also detect all changes in status of monitored points, provide event
annunciation, and actuate fire protection systems as required related to the TERMINAL. The MFGCP shall receive signals from manual fire alarm call stations site-wide via the network. A signal shall be transmitted based on the location of the MAC station activated through sirens located outdoors and flashing strobes located indoors in the high noise building or area, all over the site to inform personnel of the emergency condition and its location. In addition, initiation of a Manual Alarm Call (MAC) shall result in an alarm being raised at the PCS HMI, no other automatic action should take place at this point.
The MFGCP shall include an approved releasing module for inert gas extinguishing system activation and other fire protection systems (as applicable). The MFGCP shall monitor flammable or toxic gas and LNG leak alarm input signals.
The MFGCP shall monitor field fire and gas monitoring devices and all manual release pushbuttons, and status notification of solenoid valves and pressure switches of water spray and foam systems in the process areas (as applicable).
The MFGCP shall be programmed to shutdown or operate in re-circulation mode the building HVAC system during a fire or gas condition, as defined in the detailed engineering phase.
The FGS system shall provide the following response capabilities: Fire and gas control panel indication
Subsequent fire alarm conditions to include at least 5 previous events starting in order with the highest priority.
Inert gasextinguishing system activation
Water spray system activation from pressure switches
Shutdown and/or re-circulate HVAC and electrical power (except for life safety purposes)
Activation of PA/GA Tone Generator and strobes units in local buildings
Activation of plant emergency communication system and activation of sirens, and PA/GA and strobes, site-wide.
6.3 SER Hardware
All necessary SER hardware and software shall be designed and integrated in the FGS.
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6.4 PLC System
6.4.1 General
The FGS PLC System redundancy shall be achieved by the fault-tolerant design of the system logic solver. All components shall be redundant such that no single point of failure will deem the system inoperable The FGS PLC shall be provided with redundant:
- Power supplies - CPU's
- Internal communication paths/busses - External communication paths/busses - Input/output cards
To prevent faults within a rack, affecting the performance of the bus or any other rack, the electronics of each rack shall be optically isolated from the PLC highway communication bus.
To achieve the required level of availability and allow online maintenance, it sha ll be possible to remove and replace any of the cards from the PLC without effe cting its operation.
6.4.2 Central Processing Unit (CPU)
Each CPU shall have its own power supply, clock, RAM / EPROM memory, and parallel interface for access for programming units.
PLC CPU's shall run synchronously. It should be possible to remove or replace a single clock without affecting operation.
The clocks should synchronize automatically at power up of the system or after replacement of a single clock card.
6.4.3 Memory
The program memory contained in each CPU shall be “Flash EEPROM”. Timers should be memory resident. They should be started, stopped, reset and scanned under program control. The timers shall be capable of adjustment between tenths of seconds, minutes, and hours.
For pulse inputs to the IPS, the PLC scan rate shall be such that the minimum pulse length is at least two cycles.
For every workstation, programming facilities shall be provided to transfer the FGS functionality into memory.
6.4.4 System hardware
The FGS PLC hardware shall be housed in system cabinets. They shall contain I/O cards, power supplies, terminations, trunking, panel wiring, system cable sockets etc.
6.4.5 Diagnostics.
FGS hardware shall be provided with self diagnostic facilities. Diagnostic data and results available from the self testing mechanism shall be displayed on the PCS workstation. Failure messages shall be available in the system cabinets for the maintenance engineer. The messages shall contain sufficient information for defective card replacement. Apart from the message display, full diagnostics shall be accessible through the screen of the engineering workstation. Input / output status shall also be available on the engineering workstation. Live update of the functional logic diagrams shall assist in system troubleshooting. An overview of system failure messages and diagnostics is required.
6.4.6 System Cabinets
FGS cabinets shall comply with A3CA-06011-270-70003 “Specification for Control Panels”.
6.5 Engineering Workstation
6.5.1 The main FGS system cabinet located in the CCR AIR shall contain a HMI for engineering and maintenance. A desktop PC engineering workstation shall be provided in the CCR. The engineering work station shall have access to the complete FGS system.
6.5.2 FGS System shall be capable of communicating with the PC workstations for performing the following functions:
- On-line & Off-line configuration - Application Programming - On-line Human Interface
- Standard & Custom display development - System diagnostics display
- Auto documentation
Security features must exist in the system to prevent inadvertent and unauthorized access.
6.6 MIMIC Panel
6.6.1 The Mimic Panel in the CCR for the FGS system shall be a 52” LCD monitor. The display will utilize the graphical style to indicate the status and alarm for the plant wide area. The graphics will be the same as on the VDU operator station. The MIMIC display will normally show only an overview of the plant FGS information.
6.7 Main Distribution Frame (MDF) Cabinets
MDF cabinets shall be used for marshalling field cables to system cables and are
located in the FARs and AIR. MDF cabinets will also house interface components such as:
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- Isolator amplifiers - Proximity amplifiers
- Detector Interface modules - Terminals
- Cable - and wire supports
6.8 Cabinet Mounted Panels
Dedicated switch panel(s) shall be provided, designed for flush panel mounting in the relevant section of the main control cabinet in the CCR.
The panel(s) shall be supplied with back lit switches and be logical grouped together by area zone.
CCR control panels FGS related switches shall be directly wired to the main PLC cabinet located in the MCR AIR.
Contractor shall ensure that all cabinet mounted panels are equipped with a common lamp test pushbutton.
6.8.1 Maintenance Override Panel
A maintenance override panel shall be provided. 6.8.2 Deluge, Foam and Siren Activation
Activation of fire fighting systems is normally a local operation. The activation of fire fighting systems shall be capable from the PCS/FGS VDU operator control panels. The panel shall also contain back lit activation / resetting switches for plant located beacons and audible alarms. The panel shall be designed such that its layout is representative of the FGS area zones.
Deluge and foam activation switches shall require double action.
6.9 Input / Outputs Structure
6.9.1 General
Fire and gas detection instrumentation that are classified as “Safety critical I/O circuits” shall be designed "fail-safe" and implemented such that the system automatically reverts to the least hazardous condition in case of failure of system logic, inputs, power sources etc. This requirement shall be realized by applying a "de-energize to trip" design.
To avoid revealed failures, in cases where non "fail-safe" elements are used, energize to trip redundancy with self checking and / or comparison techniques shall be used to determine loop short circuit and open circuit failures. Signal types belonging to this group are:
- Manual Call Points
- Proximity switches (for FGS function) - Smoke Detectors
- Heat Detectors
Where required, intrinsically safe galvanic isolation shall be provided between the FGS and field signals.
6.9.2 Signal Categorization
24 V(dc) floating power supply should be galvanically separated from the logic components.
A FGS loop shall always be powered from the FGS power supply. Voltage free output signals communicating with other systems shall be powered by the receiving system (e.g. PCS, etc).
Power supply fusing for I/O cards and output circuits shall be separately fused, based on logic groups (Logic groups defined by the Process Unit area zones).
For redundant I/O cards, each rack shall be separately fused. Short circuiting of one output shall not affect other outputs.
Contractor to ensure that FGS interface signals to PCS / SIS shall be correctly powered and segregated
It shall be possible to remove I/O cards without disturbing the signal wiring. The card connection can be either via plug and socket or terminals
System I/O can be divided into: a) safety critical
b) non safety critical signals.
a) Safety critical signals are those that assure the safety integrity of the plant. Signals to / from the system shall either be via redundant fail safe serial data links or hardwired.
Typical safety critical signals are: - Deluge and Horn manual initiators.
- Detectors and SOV in and output signals. - Trip initiating signals from other ICS equipment . - Machinery protection FGS related-signals. - Plant visual and audible alarm initiators. - Maintenance Override (MOS) enable inputs.
b) Non critical signals to / from the system may either be via serial data links or hardwired. Non safety critical signals i.e.: alarms, indication, sequence of events (SER), reset switches and maintenance override switches shall comply with the following:
- Hardwired non safety critical circuits shall be arranged so that probable failure modes e.g. cable/termination faults, power supply loss, etc. will not cause shutdown or prejudice the systems safety integrity.
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- Signals routed via serial data links shall not cause shutdown or prejudice the systems safety integrity.
Communication of non safety critical signals between the FGS logic system (sub-system FAR PLC's) and the CCR (FGS control panels) shall be routed via fault tolerant fiber optic BUS.
6.9.3 Input Modules
Analogue input modules shall be designed to accept a variety of signals. LED indicators shall be provided on the front of the circuit board, visibly showing the status of the field input circuits.
Input card design criteria:-
- Selectable to act as passive or active power source - Floating from earth.
- Open circuit detection - 24 VDC.
- Short circuit proof. - Megger proof (500 V).
The input card shall be capable of providing power for the following types of input signals:
- Analogue transmitters (1-5 Vdc and or 4-20 mA) - Contacts
- Low current signals - Pulse signals
Where redundant analog input signals are implemented, the PLC shall initiate an alarm if there is more than 2% difference between input signals being read by the processor from each signal in the redundant pair. When a 2% deviation alarm exists and a card failure has not been detected, the analog input closest to the trip setpoint shall be used by the processor for logic functions. In the event of an input card or processor failure, the remaining correct analogue input shall be used for safeguarding logic functions and transmission to the PCS. Input module requirements for the PLC shall support “Line monitoring function, end of line resistance”. The I/O shall be the type that supports this function.
All transmitter input signals used for logic processing shall be transmitted to the PCS via serial communication. Redundant inputs for one transmitter shall be considered as one signal to be transmitted to the PCS.
The modules shall be key coded, relative to type, to prevent accidental damage to the printed circuit boards in the event of incorrect connection. The location and type of card shall be clearly indicated on the equipment.
6.9.4 Output Modules
Output card design criteria :-
- LED indicating output energized.
- Selectable to act as passive or active power source - Floating from earth.
- Open circuit detection
- Potential free contacts, rated 24 VDC, 1 A. (goldplated or hermetically sealed)
- Megger proof (500 V).
The output card shall be capable of providing power for the following types of output signals:
- Digital 24 V(dc) max. 10 VA). - Serial data link
Lamps 24 V(dc) output for MOS Horns and beacons
For digital outputs to SOVs, power to the field shall be provided from the MDF field power supplies.
The modules shall be key coded, relative to type, to prevent accidental damage to the printed circuit boards in the event of incorrect connection. The location and type of card shall be clearly indicated on the equipment. Output module requirements for the PLC shall support “Line monitoring function, end of line resistance”. The I/O shall be the type that supports this function.
6.10 Local Fire & Gas Control Panel
The Local Fire and Gas Control Panel (LFGCP) shall have the similar functions as the MFGCP and act independently to detect all changes in status of monitored points, provide event annunciation, display status and provide acknowledgement of all events occurring within its monitored building.
The LFGCP shall be capable of controlling all alarm functions within each building. Unoccupied buildings with only a few fire detection devices may be added to the nearby addressable signal circuit by terminating at a local junction box inside the building.
The building audible warning and flashing strobes units shall operate as a general fire alarm condition throughout the building of incidence.
System Requirements
The LFGCP shall accept, process and evaluate the following types of signals: Addressable analog smoke detectors (buildings)
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Addressable heat detectors (buildings)
Addressable manual fire alarm stations (MAC) in buildings
Inert gas extinguishing system pressure operated switch contact (buildings) Sprinkler system water flow alarm pressure switch (buildings)
Water spray systems water flow alarm pressure switches
Circuit fault monitoring of building signaling circuits shall include the following characteristics
Signaling line circuit open condition Signaling line circuit short condition Signaling line circuit ground condition
Excessive electrical "noise" on the signaling line circuit
Ability to identify the location of short and open circuit conditions Ability to identify the location of short and ground conditions Detector or device missing conditions
Improper device type at a specific address Un-configured device at an address Multiple devices at the same address
The system shall provide point isolation by a single point or group of points. The system shall ignore signals from input devices when isolated. The system shall annunciate and remain in a trouble state while any fire alarm device is isolated.
The system shall provide identification of point type, location and status. Each addressable and analog fire alarm device shall have a field assigned unique minimum 32 character device location message. The system shall provide addressable indicating circuit modules used to activate local notification appliances in each building. The system shall provide addressable indicating circuit modules used to activate local notification appliances in each building.
6.11 Earth Leakage Detection
Earth leakage detection shall be provided. It shall consist of a detection/alarm system, which continuously monitors and alarms if one of the connected circuits has an earth fault.
This feature shall be implemented for each field power supply feeder to a single field circuit. Upon earth fault detection a local lamp shall illuminate inside the MDF cabinet and a common alarm shall be transmitted to the PCS.
An important purpose of the earth leakage detection system is to identify solenoid faults in the field.
6.12 System Segregation
The design of the FGS structure shall enable maintenance, testing and card replacements to be carried out without disturbing other FGS functions.
Plant area zones shall have their control and I/0 processing hardware separated and segregated. Signals shall be distributed throughout the I/O processing hardware such that common mode failures are minimized.
Similarly, redundant cards shall be located in different racks.
Segregation and assignment of signals during the design phase shall include sufficient margin to finally provide the required level of spareage.
7.0
FUNCTIONAL REQUIREMENTS
7.1 General
The functional design of FGS system shall be based on the following project documents:-
- FGS Cause and Effect Diagrams (By CONTRACTOR) - Piping and Instrument Diagrams (P&ID) for Fire Fighting
- Fire and Gas Plan Drawings
- SHE requirements in the Project Specification, Annex J, section 12.
The FGS shall be operational at all times, even during total plant shut-down. All FGS detectors, alarms and associated equipment shall be electrically supplied by an un-interruptible power supply (UPS).
Fire protection system shall have the capability of being initiated both manually and automatically via the fire detection systems.
7.1.1 Functional Structure
Each protective system shall operate independently from other sub-systems. If safety relevant signals have to be routed from one subsystem to another, they shall be hardwired or routed over the FGS System Bus and not routed via PCS communication link.
7.2 Overview
7.2.1 Detection System
The function of the detection system is to promptly identify any abnormal conditions resulting from a fire, or gas (LNG) escape and to provide signals to other sub- systems to initiate warning alarms and protective actions.
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Suitable flammable gas, toxic gas, low temperature, and fire detectors shall be installed in strategic locations throughout the plant. The Fire and Gas detectors shall have integral signal processing and switching capability to provide either 4-20 mA signal and / or volt-free contact signal inputs to the Logic System.
7.2.2 System Logic
The Logic functionality of the FGS system shall be achieved by the FGS PLC's software. The purpose of the system logic is to process input signals from the detection system and carry out the following actions :
Initiation of selective alarm and display information in the CCR and plant areas.
Enable manual or automatic activation of fire protection systems,
The logic shall be designed to minimize spurious alarms and trips whilst maintaining system integrity.
The logic system shall provide an input to a FGS SER, and shall interface with the FGS HMI console (PCS) and other FAR FGS PLC's.
Where required a hard wired interface shall be provided between the FGS PLC and the IPS PLCs within each FAR.
7.2.3 Plant Alarm and Warning System (audible and visual)
The FGS shall interface to the plant emergency communication system, activation of sirens/horns/strobes, and PA/GA site-wide plant alarm and warning system.
The plant alarm and warning system is required and shall be engineered as an independent module of the FGS system, its purpose is to receive inputs and generate audible and visual alarms to a variety of output devices. Sufficient pushbuttons / switches shall be provided, but not limited to the following functionality:
Site(s) Fire Alarm (Activation)
Site(s) Fire Alarm (All clear)
Zone(s) Gas Alarm (Activation and Silence)
Zone(s) Gas Alarm (All clear)
7.2.4 Alarm Presentation
All FGS alarm signals shall be presented on the CCR FGS and Fire Station Building control panels, logged and printed via the SER facilities.
In line with the functional structure, the following types of alarms shall be presented:
High level (LEL) flammable gas
Fire (initiated from heat, fire, smoke detectors)
LNG Leak detection
Manual Call Points
Common zone alarms shall be presented on the FGS VDU control panels Common zone alarms applicable to package units shall similarly be
presented.
An alarm management system shall be developed which achieves the following objectives:
Minimize the number of active alarms
Maximize the information contained in the alarms Obtain effective presentation of alarms
All new buildings e.g. Service building, Warehouse, AHs, FARs, Substations, etc. shall have indoor detectors and fire panels.
7.3 Human Machine Interface (HMI)
7.3.1 CCR FGS Control Panels
The HMI comprises of VDU graphic displays and hard wired switch panels. The HMI shall be the primary interface for all FGS related activities. The Mimic panel shall replicate overview displays from one of the VDU stations. All FGS protection systems and plant audible and visual alarms, shall be initiated from the control panels. The VDU graphic layout shall be a geographical representation of the whole site which shall be split into three main areas, i.e. :
The process / utility area
The Jetty Loading/Unloading areas The Truck Loading area
The Buildings area
Vendor installations which only provide common alarms, (i.e. BOG compressor, analyzer houses, sub-stations, etc.) shall be graphically identified as an individual zone.
Under normal conditions, an alarm shall be presented by a small open box; an alarm situation will change the open box into a solid box. Symbols for gas alarms shall distinguish between High and High High alarms.
Individual detector status including analogue values shall be shown on a lower graphic display and alarm summary status.
A FGS control panels shall also be provided in the Fire Station Building, this facility will be for "Read Only" purposes.
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The FGS VDUs are part of the PCS system, and as such shall be implemented as part of the PCS scope.
The VDU for the FGS shall be a dedicated set, serving only the FGS monitoring, status and control. The operation for PCS control on this panel is prohibited. Additionally, the VDU for the FGS (PCS operator station) shall support the multi-screen function (at least two), where one monitor shall be utilized as a operator screen and the other monitor shall be used as a MIMIC for the FGS for this project (these two monitors will share the same processing unit).
7.3.2 Maintenance Override Switches (MOS)
The TERMINAL maintenance override philosophy shall be in accordance with existing PTT practice.
MOS shall be provided for all FGS inputs with an exception for the following signals:
- Manual trip switches - Limit / Proximity switches
Maintenance override switches for FGS shall be implemented on basis of fire protection areas. In general, the MOS shall be configured to prohibit the activation of Fire Sirens / Beacons / Sounders and the Fire water pump(s), however alarms of circuits under MOS condition shall generate alarms in the CCR.
To apply a MOS function the following two steps are required::
- Step one the Maintenance Override Enable Switch (MOES) is activated. (see for details a) below)
- Step two the MOS is set. (see for details b),c) and d)) a) Maintenance Override Enable Switches (MOES)
Hardwired, back-lit Maintenance Override Enable Switches (MOES) shall be integrated on the PCS console. One MOES shall be provided per cause and effect fire zone.
The MOES is hardwired into the FGS logic, the operator has the facility to de-activate an override regardless the status of the PCS or communication link.
The "MOES and lamp shall give an overview of all the maintenance overrides that are currently activated
b) Maintenance Override Switches (MOS)
MOSs shall be configured in the PCS and connected to the FGS via redundant serial links. MOSs shall be accessed via the PCS graphic displays.
PCS MOS override signal shall be accepted by the FGS logic only when the MOES is in the enable position.
The "MOS set" indication lamps shall be located on the PCS console to indicate the MOS status and shall have three states:
- Off No MOS is on
- On A MOS is on but the trip initiator is in normal state (process condition is healthy).
- Flashing A MOS is on and the trip initiator is in trip state.
Output from the PCS to set MOS's shall include FGS software which prevents more than one MOS being activated per Process Unit Area zone. c) MOS activation
The PCS sends a "MOS request” via the serial link to the IPS. The IPS determines if the use of the MOS is permitted. This is only permitted if the "MOES” is in the enable position and only one MOS is selected for a particular Process Unit Area zone. If both criteria are fulfilled, the maintenance override is set and a "MOS set" signal is sent back from the IPS to the PCS via the serial link.
If the "MOS set" signal is not received within 5 seconds after the "MOS" request", then the PCS shall automatically cancel the "MOS request". The canceling of the "MOS request" shall generate an answer back alarm in the PCS to indicate to the operator that the "MOS request" has been denied. d) MOS de-activating
An activated and confirmed MOS can be de-activated via the PCS screen. The tag will change color from blinking red to black.
7.4 Serial Communications
Only standard international communication protocols shall be utilized. (Such as EIA RS-232-c, modbus RTU, RS-484, Ethernet TCP/IP)
Internal communication between manufacturers hardware may deviate from the above.
Serial Links shall not be utilized to pass critical safety related - and/or controls signals between different systems. Special attention shall be given to the testing of serial links during the FAT.
Loss of one serial link within the redundant system structure shall not lead to any malfunction.
7.5 Interfaces with Other ICS Systems
7.5.1 Process Control System (PCS)
The PCS shall be used to display and annunciate all FGS status information.
In addition to the above, other signals are required by the PCS for SER alarm displays, MOS setting and confirmation etc.
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The FGS shall provide selected inputs for initiating ESD actions. The interface to the ESD/SIS shall be hardwired outputs from the FGS.
7.5.3 FGS - Vendor Installed Package Equipment Interface Requirements
Separate fire and gas systems (sub systems) will be provided by certain package equipment vendors (e.g. compressors, analyzer houses, sub-stations, etc.). These systems shall be interfaced with the FGS system logic (PLC) within each relevant FAR.
The interface shall be hardwired and will facilitate status, common alarm and command signal data transmission to the CCR.
The systems shall provide the following signals to the FGS logic (PLC) within the relevant FAR, and shall be generic for all vendor fire and gas systems, - Outputs:
- Common Gas detection alarm (flammable and / or toxic) - Common Fire detection alarm
- Common Heat detection alarm
- Protection system activated (gaseous, deluge etc.) - System fault
- Maintenance override selected / confirmed (to CCR FGS) - Inputs:
Maintenance override selection (per initiator).
refer to section 7.3.2 for guidance on MOS application.
Package equipment vender installations which activate an automatic protective system, shall also allow for manual initiation and resetting from the CCR FGS control panels.
The manual activation (from the CCR) of these package FGS systems shall only be permitted after alarm generation and evacuation times have elapsed.
7.6 Compliance
The minimum requirement for FGS systems are as per IEC 61511
Initiators and outputs associated with the following items shall be implemented in accordance with the IEC61511 classification:
- spray systems
- fire prevention on Compressors
- Compressor shutdown
- Isolation of electrical supplies in hazardous atmospheres
Electrical instrumentation components and electronic instrumentation systems for use in hazardous areas shall be in accordance with IEC 79
7.7 Diagnostics
Diagnostic tools resident within FGS (for analyzing faults) shall be provided, allowing continuous diagnostics without influencing the FGS performance.
The analysis shall be sufficient to identify faulty cards and define the cause of the errors
8.0
DETECTION SYSTEMS
8.1 General
The number and location of detectors and their associated equipment shall be developed by CONTRACTOR during detail design and shall obtain approval from PTTLNG/PMC prior to proceeding.
The provisional quantities and location of detectors are shown on Fire and Gas Detection Plan drawings FP-001 and A3CA-A1-06011-1000-FP-002.
The detectors shall be safe for operation under ambient conditions and have vibration-proof connections. The detectors shall be suitable for location in hazardous areas. The sensors shall be built into an explosion-proof, stainless steel housing.
All fire and gas detectors for use in process areas shall be certified as a minimum for use in zone 1 areas.
All detectors shall be installed with fire retardant cable.
8.2 Flammable Gas Detection
8.2.1 General
Two types of flammable gas detectors shall be used to detect flammable gases: IR point detector and IR open path detector. Only IR gas detectors are approved for this project because they provide rapid response to gas. I) Point IR Gas Detectors
The point IR gas detectors use the properties of hydrocarbons and other gases to absorb infrared energy at certain wavelengths. Where point IR gas detectors are chosen, 20% LFL (Lower Flammable Limits) and 50% LFL should be used as respective thresholds to indicate low/high level gas.
Point IR gas detectors shall be installed near the seals of gas compressors and hydrocarbon pumps. They shall also be provided at the air inlets (e.g. HVAC) to all buildings that have potential facing flammable gas leak.
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II) Open Path Gas Detectors
The open path IR gas detectors use the same principles as the IR point detectors. A beam of light is sent from the transmitter to the receiver where it is divided and measured at two distinct wavelengths in the infrared band, one wavelength for gas indication, the other for reference. The infrared beam can be projected over 30 to 90 m long. The open path IR gas detectors provide information about the average flammable gas concentration along the path. The detector will produce the same response for a 1.5 m wide plume of 50% LFL as it will for a 7.5 m wide plume of 10% LFL. Open path gas detectors shall be installed around the periphery of the vaporizer area.
Selection of flammable gas detectors shall be suitable for anticipated types of gas release (e.g. methane).
8.2.2 Gas Detector location
The location of the gas detectors shall be defined for each individual situation, taking into account the prevailing wind direction and the presence of heavier or lighter than air gases. The detectors shall be mounted below or above the possible sources accordingly. Collecting cones may be considered when appropriate.
Point IR gas detectors shall be installed near the seals of gas compressors and hydrocarbon pumps. They shall also be provided at the air inlets (e.g. HVAC) to all buildings that have potential facing flammable gas leak.
Open path gas detectors shall be installed around the periphery of the vaporizer area
Flammable gas detector analogue signals are used to generate alarms from values set within the system. Alarms shall be implemented as follows:- Flammable gas detectors shall have 2 alarm points, 'high' (H) and 'high high' (HH). The 'H' shall be set at 20 % LEL and the 'HH' at 50 % LEL, adjustable between 0-100 % corresponding to 4-20 mA.
The alarm for infrared beam type (open path) shall be in LEL-meter.
Any single detector, detecting flammable gas above the 'H' alarm point, shall initiate an alarm in the CCR and a visual alarm(s) in the local plant area. CCR alarm indications shall distinguish between H and HH values.
8.2.3 Flammable gas detectors shall be typically located in the air inlet of: Electrical substations located within the plant area.
Field auxiliary rooms (FAR). Analyzer houses.
Air compressors.
Air intakes of building(s) HVAC system
For the above the detectors shall be arranged in a two out of two voting system. Detectors shall be mounted close together in pairs. Each detector will have two adjustable set points between 0-100% LEL.
The pre-alarm shall be obtained when either detector reaches 10% LEL. When two detectors reach 20% LEL, an alarm will be activated; the fresh air intakes will be closed and the ventilation fans stopped.
8.3 Fire Detection
8.3.1 General
The detection of a fire in its earliest stages of development is of the greatest importance if remedial actions are to be effective. Two principal forms of fire detection shall be employed:
Human (Manual Call Point) Automatic fire detection. 8.3.2 Manual Call Points (MCPs)
Manual call points shall be used to communicate fire detection to the CCR. Manual Alarm Call Points (Alarm Stations) shall be provided as a minimum based on the following criteria:
Along roads in the plant area at interval not exceeding 100 m Along roads in storage tank area not exceeding 200 m
Near or at location having a high risk such as process equipment, valve manifold, jetty head
Inside buildings, office entrance, canteen, warehouse, medical, guard house, etc.
In general, the Alarm Call Points are provided at the building exits to enable operators to raise an alarm in an emergency. Manual Alarm Call Points shall be mounted at a height of 1.2 m above floor or grade level. The Alarm Call Points may be used for other accidents or situation where the attention of Main Control Room is required in accordance with established operational procedures.
MCPs shall be of the push button type with a key to reset. 8.3.3 Automatic Fire Detection
Automatic fire detection shall be achieved by the following types of devices:- Infra-red flame detectors
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8.3.4 Ultra Violet / Infrared (UV/IR) Flame Detectors
UV/IR detectors shall be solar blind and shall be applied where fast detection of hydrocarbon fire or other flammable products with a high hydrocarbon content is required The design of the detectors shall be based on the flame flicker principle, i.e.. the detector responds to the flickering effect of hydrocarbon fires and are not suitable for detection where smoldering occurs.
Infrared flame detectors shall be installed in and around process area, on the roof of LNG storage tanks, and on the jetty head.
8.3.5 Heat Detectors
Fixed temperature heat detectors are usually used inside the buildings. Rate compensated heat detectors shall be provided in the areas where smoke detection is impractical such as in the kitchen, maintenance shop, or emergency generator room. These detectors are designed to activate at both a fixed temperature and fast thermal rate of rise due to fire growth. 8.4 Buildings
8.4.1 General
All building related fire and safety facilities shall be provided in accordance with project specifications.
Fire and gas sensors located in AIR's, substations and analyzer houses, etc., shall be individually connected to the sub-system FGS hardware.
The Contractor shall ensure that all areas within the buildings are adequately covered with detectors. The CONTRACTOR shall develop detectors layouts during detailed design and obtain approval from PTTLNG/PMC before proceeding.
Building protection detectors shall be displayed on a local panel at the building entry point.
The LNG plant's AIR located equipment shall be protected with an early warning smoke detection system.
8.4.2 Smoke Detectors
Smoke detectors shall be either fixed head or reflection type. Smoke detectors shall not be provided for indoor cable trays. The Contractor shall ensure optimum operation of the detector system.
8.4.3 Combined Optical Smoke / Heat Detectors
Solar blind light reflection type of fixed head type detectors shall be used for the detection of smoldering fires in buildings.
They shall be installed in enclosed spaces such as laboratories, computer rooms, workshops, battery rooms, warehouses, offices, FARs etc.
