The Necessities of Fire and Gas Detection System On Offshore Platforms

Ir. Gan Chun Chet

THE WORLD WE LIVE IN TODAY(1)

• Today, we live in a real world that implements (simulated) results, a simulated world in actual beginnings, depend on circumstances.

• Environmental conditions are carried out with data recorded to assure the situation.

• Are these worlds, that have been created, actually real or simulated?• Have humans invention harmed the environment.• Some would said that their inventions are working in harmony with nature

while some will say that their inventions has been damaged by the environment that they lived in.

• That the power of nature against human inventions (e.g. tsunami, hurricane, heavy snowfall, flood, etc.)

Natural Disaster2011, Sendai Japan.

THE WORLD WE LIVE IN TODAY(2)

• At present, engineering based on human invention is based on a simulated world where it all begins. Models are scrutinized at various organization, and some are applied in the petrochemical or oil and gas facilities.

• Inventors of internal combustion engines linked back to 2nd century in Switzerland where a crank shaft or connection rod was documented. Later used and developed up to present stage as a reciprocating device.

• Henry Ford the founder of Ford Motor Company sponsor the development of assembly line technique of mass production.

• Today, we see internal combustion engines massively in used with variety of lean gas mixture designs.

Ford assembly line 1913

Roman crankshaft dated to the 2nd century AD. The right handle is lost.

A WORLD THAT SOME LIVE IN

• In a place far beyond, lives another system that seems to be in a conducive nature. The atmosphere is soothing to a person BUT MIGHT NOT if there is a catastrophe.

• It is a situation that is beyond our imagination, Piper Alpha Disaster (1988) at North Sea.

• In a fire situation, or a gas leak scenario, is it real? Or is it simulated?

Operator : Occidental Petroleum

TYPES OF FIRE AND GAS DETECTION SYSTEM ON OFFSHORE PLATFORM(1)

• What are implemented:• 1) In some application, the complete Fire and Gas Detection SYSTEM are

required at a huge cost for implementation for the safety and wellbeing of a defined population, e.g. including Motor Control Centre MCC/Switchgear Room, FM-200, Battery Room, and Control Room.

• 2) Some requires only a SUB-SYSTEM, for smaller group, where it will be safe for all in the vicinity (entry from process into utility areas/control building and addressable system to protect the personal in living quarters).

TYPES OF FIRE AND GAS DETECTION SYSTEM ON OFFSHORE PLATFORM(2)

• 3) Or probably requires only a fire watch (in quarters) and a portable detector that accompanies the person to detect a gas leakage in its define walk (utility) on occasional visits to the platform.

• 4) Other method of studies : To apply noise detectors or microphone, due to small leakages. This is use measure the amplitude of the noise as the frequencies are visible on the spectrum.

A Noise Spectrum Tool; SpectrumView

FIRE AND GAS SYSTEM BLOCK DIAGRAM (configuration of hardwired signals for initiation/alarm)

APPLICATION OF VARIOUS FIRE AND GAS DETECTORS

FLAMMABILITY TRIANGLE

• WHAT IS FIRE AND GAS DETECTION ?• It is the method of detecting the presence of flammable/toxic gases

and/or fire in identified areas of risk• WHY IS IT IMPORTANT ?• To protect and safeguard• Personnel, equipment and the environment• POSSIBLE CAUSES OF GAS LEAKS AND FIRES ?• Gas leak from pump seals, flanges, etc.

– Wear and Tear,– Vibration, etc.

• High pressured flammable gas will shoot out from pressurized pipeline or equipment from point of leakage

• Possibility of an explosion or a fire (see flammability triangle)

Figure 1 : Flammability Triangle

Figure 3 : Methane Gas Explosive Limits

Figure 2 : Early Gas Detection Warning Level

GAS DETECTION : The ability to detect lean concentration of METHANE gas at an early leakage stage before a catastrophe.

TYPES OF GAS DETECTORS

• Gas detectors – Infra red, electrochemical, catalytic (point detectors)– Infra red (line-of-sight)

Model Polytron 2IR

Model Pulsar

Model Polytron FX

Model APEX

Model ECLIPSE

Model OPECL

ANIMATION OF A GAS LEAK (animation)

V-1WIND

GD-1GD-2

Tx

Rx

Line of Sight Gas Detectors

FLAME DETECTION : The ability to detect infrared flame when it appears

Extract from NFPA 72

Model S251f+ (Triple IR)

Model X3301 (Triple IR)

TYPES OF FLAME DETECTORS

• Flame detectors– Infra red (triple 3IR) – Ultraviolet (UV)– Ultraviolet and Infra red (UV/IR)

PLACEMENT OF FLAME DETECTORS (animation) FD-1 FD-2

V-1

FD-3

FIRE AND GAS DETECTORS LAYOUT

FIRE AND GAS MAPPING

A fusible plug is a threaded metal plug, which has a tapered hole drilled completely through its length. This hole is sealed with a metal of low melting point, usually lead or tin.

PNEUMATIC FIRE DETECTION SYSTEM

LOCATION OF PNEUMATIC PLUGS

FUSIBLE PLUG LOOP SCHEMATIC

TYPES OF SMOKE AND HEAT DETECTORS

• Smoke detectors – optical– ionisation

(being phased out due to stringent disposal requirements of radioactive substances)

• Heat detectors – rate of rise– fixed

Model 601P

Smoke Detector

Model 601H-R Model 601H-F

Heat Detector

Courtesy of THORN

PROGRAMMABLE LOGIC CONTROLLER

Fail Safe Controller (FSC)Human Machine Interface (HMI)

Addressable Fire Alarm Panel (AFAP)

Part of the Shutdown System SDS

Part of Fire Alarm System FAS

Part of Fire and Gas System FGS or Process Control System PCS

ATTACHMENTS

• Article (Technical)• 1. Fire and Gas Detection – A Safeguarding System Worth Investing,

Institute of Engineers Malaysia, Jurutera Magazine, 24 May 2008• 2. Reliability of Gas and Flame Detectors on Offshore Platform, Institute of

Engineers Malaysia, Jurutera Magazine, p25, Nov 2013• Data Sheet (Technical)• 1. Sample of Gas Detectors Datasheet• 2. Sample of Flame Detectors Datasheet