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Non process buildings


Two H2S detectors shall be provided at the air intake of new HVAC system (if any) depending on detection philosophy.

When one detector reaches 10 ppm, it shall give:

An individual visual alarm on the concerned control or matrix panel showing the location of gas detection.

An audible and visual (orange flashing light) alarm (if any) at the entrance to and in the concerned building

An audible and visual alarm in the control room.

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation

When 1 out of 2 detectors reach 20 ppm, the following actions shall be added

An individual visual alarm on the concerned control or matrix panel showing the location of gas detection.

An audible and visual (orange flashing light) alarm (if any) at the entrance to and in the concerned building

An audible and visual alarm in the control room.

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation

The ventilation system shall be stopped and dampers closed.


SO2 detection


SO2 detectors shall be used in sulphur handling units as fire detectors:

SO2 is a product of sulphur combustion. When 3 ppm is reached, each detector shall give:

A general audible alarm in the IES associated with the concerned plant area.

An individual visual alarm (red flashing light) on the concerned matrix panel showing the location of gas detection.

An audible and visual alarm in the control room

An audible and visual alarm in the maintenance workstation

An audible and visual alarm in the fire station.

A common audible alarm and a common visual alarm (red flashing light) in sulphur handling units.

Concentration of SO2 gas shall be measured and displayed over the selectable range of 0-20 ppm.

SO2 detectors shall be provided in sulphur handling units for liquid sulphur pumps, sulphur sump, sulphur plant incinerators, reaction furnaces.


Cl2 Detection


Cl2 Detectors shall be provided to chlorine packages and connected to the Fire & Gas system.

Closed circuit television monitoring systems


A closed circuit television system shall be supplied.

Closed circuit television and monitoring system shall be in accordance with

Manual call / egress gate points

A system of manual call points and egress gate points for initiating a fire alarm shall be provided as part of the plant fire protection system.

Manual call points connected to Fire and Gas system shall be clearly recognized, provided with signs and located as follows:
Along roads in the plant area at intervals not exceeding 50 m, preferable at or near lampposts. Inside the plant and positioned:

At the exit doors of IES

Along logical escape routes

At each exit door of electrical substation

At each exit door of operator shelter

Near sulphur loading bay.

Also manual call points shall be located at the emergency exit point from process areas (usually the normal entrance and exit).

Egress gate points (box containing key for plant fence door) shall be located as follows:

At each egress gate inside plant

When there is a double fence for plant and for sulphur truck road, at each egress gate outside plant and at each egress gate for sulphur truck road.

When operated, manual call points and egress gate points shall give:

A general audible alarm in the building or IES associated with the concerned plant area.

A general audible and visible (red flashing light) alarm in the concerned process plant area.

An individual visible alarm (red flashing light) on the matrix panel.

The operation of the manual call points and egress gate points shall be sent via the data highway to the Fire and Gas Detection System in the fire station and control room, it shall initiate:

An audible and visual alarm in the Control Room,

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation


Fire detection


Fire detection in open area

Fusible plug detectors shall be installed on equipment protected by a fixed deluge system. These shall activate the concerned deluge system. The pressure drop in the fusible loop shall be detected by one low-pressure switch (PSL) and the firewater flow rate in the deluge pipe shall be detected by one high-pressure switch (PSH). The PSL shall give:

A visual alarm (red flashing light) on the matrix panel

An Air low-pressure alarm in the control room

An audible and visual alarm in the fire station

An audible and visual alarm in the maintenance workstation

An audible and visual alarm in the concerned process area

The PSH shall give:

A general audible alarm in the concerned IES.

A visual alarm (red flashing light) on the matrix panel.

A High water pressure alarm in the control room

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation

A common audible alarm and a common visual alarm (red flashing light) in the concerned process plant area.

A pressure transmitter shall be added on deluge system fusible loops. In case of Low air pressure in the fusible loop, this transmitter shall send a signal to the plant DCS.

Fire detection in the buildings


Optical smoke detectors and heat detectors rate of rise type shall be used.

When executive action is expected, voting is required based on two separated loops with a maximum of 6 detectors per loop in case the system is not addressable. If executive action is not required, only one loop shall be installed with a maximum of 6 detectors per loop in case the system is not addressable.

Heat detectors shall be installed in offices, smoking areas, HVAC rooms of IES and substations, battery rooms of IES and operator shelters.
Smoke detectors ionization type shall be installed in building corridors, WCs, UPS rooms of IES, control room of IES, battery rooms, switchgear room of electrical substation, power generation enclosures and diesel driven engines enclosures. The fire detection by one detector on one loop shall give:

A visual alarm (red flashing light) on the matrix panel in IES associated with the concerned building with the system buzzer.

A general audible alarm in the IES associated

An audible and visual alarm (red flashing light) at the entrance to and in the concerned building

An audible and visual alarm in the control room

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation

The fire detection by two detectors on two separate loops shall give the following additional actions:

A general audible alarm in the IES associated

An audible and visual alarm (red flashing light) at the entrance to and in the concerned building

An audible and visual alarm in the control room

An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation
Stop ventilation system and close fire dampers of the concerned building

Release after an adjustable ‘time delay’ the automatic extinguishing system allocated to the concerned loops (when applicable).


Where there is an executive action, 2 detectors shall be installed per 50 m² (as per BS 7273). Which on separate loops. When installed for alarm only, one detector per 50 m² with a maximum of 6 detectors per loop shall be provided.

The smoke and heat detectors in the enclosed rooms shall be looped separately i.e. to include all the smoke detectors in the ceiling void to be in separate loops, and all the smoke detectors in the floor void to be in another separate loops i.e. not to club detectors at ceiling void and detectors from floor void in the same loop. A remote indicator shall be provided for each detector installed in the ceiling and the floor.

Fire detection for packages

For the flammable gas detection (distribution and installation) for packages refer to “Instruments furnished with packages”

At least two rates of rise heat detectors shall be optimally located in each enclosure compartment of the packages.
When any detector is activated, the following alarm shall be initiated:

A general audible alarm in the IES associated with the concerned plant area.

The signal shall be sent via the data high way to the Fire and Gas Detection system in the fire station and control room; it shall initiate:
An audible and visual alarm in the fire station.

An audible and visual alarm in the maintenance workstation


When two detectors are activated, the following alarms and actions shall in addition be activated:

A common audible alarm and a common visual alarm (red flashing light) in the concerned plant area,

An audible and visual alarm in the Control Room

An audible and visual alarm in the Fire Station

An audible and visual alarm in the maintenance workstation
Shutdown and electrical isolation of the machine,

Stop fuel supply (when applicable) Shut-down of the ventilation system and closure of the fire dampers (when applicable)

Release after an adjustable time delay of the CO2 extinguishing system (30 sec).
Fire detection in Non process buildings

Fire detection philosophy is fitted to installation. For each building, the fire control panel shall be provided.

If necessary, fire detectors shall be relocated or recovered.

One detector obtains executive action or one loop (no voting by two separated loops). The fire detection by one detector or one loop shall give:

An individual visual alarm on the concerned control or matrix panel associated with the concerned building

An audible and visual (red flashing light) alarm (if any) at the entrance and in the

concerned building.

An audible and visual alarm in the main control room

An audible and visual alarm in the in fire station

An audible and visual alarm in the maintenance workstation

The ventilation HVAC system shall be stopped and dampers closed.

Basis For A Fire Protection Water System


Firewater shall be readily available at all the appropriate locations, at the required pressure and flow. Firewater should not be used for any other purpose.

Fire water rate


Fire water rate design criteria

The quantity of water required for fire protection shall be calculated based upon the criteria of section


Firewater ring main system

Firewater ring mains of the required capacity shall be installed to surround all processing units, loading facilities, warehouses, workshops, and utilities. Normally, these units shall also be bounded by service roads. Large areas shall be sub-divided into smaller sections, each enclosed by firewater mains equipped with hydrants and block valves.

The minimum size of fire water main shall be 8”(200 mm)

The firewater mains shall be provided with full bore valve-flushing connections so that all sections and dead ends can be properly flushed out. The flushing connections shall be sized for a fluid velocity in the relevant piping of not less than 80% of the velocity under normal design conditions, but not less than 2 m/s.

Firewater mains shall be installed underground in order to provide a safe and secure system. Depth of cover shall not be less than 1.1 m. A pressure transmitter shall be installed on the main header every 500m and connected to the Plant fire Alarm System.
The firewater mains network pipe sizes shall be calculated using an approved computer program. The complete calculation shall be based on design rates at a minimum pressure of 7 bar g at the take-off points of each appropriate section, and calculations made to prove that pressure drop is acceptable with a blocked section of piping in the network. The firewater ring main pressure shall be such that under fire conditions a pressure of 7 barg exists at the most remote location under the corresponding design flow conditions. The maximum allowable velocity in the system is 3.5 m/s.
Firewater mains - installation and material selection

Piping materials shall conform to Design Specification.

At each main tee, the number of isolation valves shall be the number of branches minus one. Block valves shall be incorporated in the ring main system so that sections can be isolated for maintenance, etc. These sections shall be selected so that the number of consumers is not more than 6. The valves shall be butterfly / gate valves with position indicators. The firewater ring main systems shall be equipped with hydrants, monitors, hose reel stations and deluge valves.

Hydrants


Firewater mains shall be provided with permanent hydrants, located in strategic positions around utilities units / areas. In the process areas, hydrants shall be provided with a top mounted water monitor. Each hydrant shall have an isolation valve in addition to the hydrant valve.

Hydrants shall be as per ones with 4 x 2 1/2 outlets.

Take-off points shall be on the side of the header.

Hydrants connected to buried lines do not require bottom drains.

The spacing between hydrants shall not exceed the following:

Around utility areas 70 m (3 length of hose)

Around process unit, 50 m (2 length of hose)

Hydrants shall be readily accessible from roads and located in such a way that possible damage by road traffic be minimized, provided with a guard post and concrete drainage area. The location shall not be less than 1.5 m from the edge of the road shoulder and at least 12 m from road crossings, sharp road curves, and buildings or other structures.


Monitors


Firewater mains shall be provided with permanent monitors spaced note more than 50 m around processing units. Monitors to be installed on firewater hydrants shall be located at least 15m away from protected equipment to ensure accessibility in case of a fire. Rotation, elevation and nozzle adjustment shall be done manually without gears. When monitors are in use, it shall be possible to leave the monitor unattended operating safely. The monitors shall comply with the following requirements:

Upstream of the mounting flange, each monitor shall be provided with a butterfly valve accessible from grade.

The monitor shall have a capacity of at least 120 m3 / hr at 7 barg. Larger capacity monitors require the Company approval.

Min /max operating pressure to be respectively 6 /16 barg.

The water monitor shall have a 2-½ inch threaded end allowing easy connection of an adjustable nozzle of the constant flow fog to jet stream type.

Monitors shall be of such design that the hydraulic forces (jet reaction), considering pressure surges when opening the upstream block (butterfly) valve, are balanced.

The monitor shall be able to rotate 360 degrees by means of a turret, lockable in any position. Elevation setting shall be from 15 degrees below to 85 degrees above the horizontal i.e. a total 100 degrees.

Rotation and elevation movement lever operable, setting and locking shall be easy. The moving parts shall be fully protected / enclosed against sand and salt spray. Monitors and nozzles shall be of materials and coatings suitable for use with seawater in outdoor weather conditions.

Monitor shall be tested and certified by an independent authority to be approved by the Contractor. The manufacturer shall provide a copy of the certified test report. As a minimum the test report shall include the following data:

Foot print (width x depth), i.e. area where 80% of the total water flow hits the horizontal plane through the raised face of the mounting flange for jet and 30 degrees fog (both at 30 degrees elevation), Throwing distance (trajectory) measured from nozzle exit to center of foot print, Pressure at monitor inlet flange, Flow rate, Diameter of used hose connection, Wind speed and direction,

Angle between wind direction and water trajectory.

Firewater supply


Firewater supply storage shall be a volume equal to 12 hours consumption at maximum main pump flow rate.

The well water being saline shall serve an emergency source only. The complete fire water main system must be flushed with fresh water after being used for emergency purpose.



Firewater pumping facilities


Firewater shall be provided by pumps of the horizontal split case centrifugal type (the number of pumps shall be according the worst case scenario).

Firewater pumps are installed in a location considered to be safe from the effects of fire, clouds of combustible vapour and from collision or crash damage by vehicles.

Firewater pumps shall be electric driven with one diesel driven (backup). Pumps as well as drives shall comply with the requirements of NFPA20 and applicable Design Specifications.

The power of the drives for both main and stand-by units shall be so rated, that it is possible to start the pumps against an open discharge with pressure in the fire-water ring main system under non-fire conditions, normally at 2 to 3 barg.

When the pressure in the firewater ring main system drops below the minimum required static normally approximately 2.7 barg, the first firewater pump shall attempt to start.

Thereafter, at 30 seconds intervals, the next designated available pump shall also attempt to start if the system pressure is less than 10 barg.

Contractor shall define the start-up logic. The automatic starting facilities shall be configured to allow system testing including simulation of alarm activation while the standby system remains operational.

Manual starting of each pump unit shall be possible at the pump, at the control room and at the fire station. Manual stopping of each pump unit shall only be possible at the pump station.

The operation of the main firewater pumps shall actuate an alarm in the control room and fire station panels indicating system pressure.

The system shall be protected from surge and hammering. Hydraulic studies of the system shall be performed to ensure that water hammer does not occur at all expected operating conditions.

Hydraulic calculations shall be performed using approved software to verify that the firewater pumps capacity (flow rate and pressure) is satisfactory to achieve the required flow rate in each area at 7 bars g minimum. (This shall apply for both electrical and diesel driven pumps)

The response time for starting the firewater pumps and for feeding the plant area shall be measured on site for adjustment if necessary.

A ring main surge analysis shall be performed.

The diesel engines of the firewater pump shall meet the requirements of NFPA 20 and the applicable Design Specifications. The following additional requirements shall also apply: The capacity of the diesel storage tank shall be such that the engine can operate on full power for at least 12 hours.

The tank shall be installed at a safe distance from the engine with the bottom at least 0.2 m above the suction valve of the diesel injection pump or as specified by the pump vendor. The tank shall be provided with a sump, an expansion dome, a level gauge and a low level alarm which shall sound when the level of the diesel has reached the ‘2-hour diesel’ remaining level. The tank shall be provided with one connection for refilling directly from diesel distribution network. A clutch shall not be installed between diesel engine and pump. The discharge line from the pump shall be fitted with a check valve, a test valve, a pressure gauge and a block valve with a locking device. The test line arrangement shall allow testing of either pump while the spare pump remains available for service. The test valves shall have a common return line with a flow-metering unit. Each pump shall be connected separately to a common manifold. The pump discharge manifold shall be connected to the firewater ring main system by a separate pipeline with a block valve of the same size as the ring main. The firewater ring main pressure shall be such that under fire conditions a pressure of 7 barg exists at the most remote location under the corresponding design flow conditions the maximum allowable velocity in the system being 3.5 m / s. Batteries for the diesel pump and the fire pump controllers shall be located in normally air-conditioned areas.

Deluge systems


Hose reels


The hose reel stations for process units shall be designed

The hose reels for buildings shall be designed as the hose reel stations but without the associated foam station as for process units.



Foam Compound Storage


Foam compound Storage is necessary. The Contractor has to determine the suitable quantities and the mode of storage.


Portable and Mobile Fire Fighting Equipment


Portable and mobile equipment, in accordance with the requirements shall be

available at the first line of attack and for the backing-up of fixed fire protection systems.



Hose boxes


Hose boxes shall be installed at every other hydrant or monitor. Each box shall contain 4 fire hoses and 2 water branch pipes.


Fire / Safety point shelters


A weatherproof fire point shelter shall be located near each process and utility unit at non-hazardous area duly equipped with the following:

8 fire hoses in weatherproof cabinet.

2 x 75 kg ABC wheeled dry chemical powder fire extinguishers.

3 spray / jet nozzles.

1 Foam making branch pipe complete with pick-up tubes and probes.

5 Jerry cans each contains 25 liters foam (Fluoro-protein foam FP 70 - AFFF type may be considered as an alternative).

2 Breathing Apparatus sets 30 min in weatherproof boxes.

1 Stretcher.

1 First Aid Box

At chemical handling areas, the fire point shelters shall also be equipped with chemical resistance gears (boots, gloves, face shields and cover-alls)



Fire extinguishers


The extinguishers shall be positioned within process units and along walkways such that the travel

distance between the extinguisher and the possible fire hazard is limited to 15 meters for process units and 30 meters for other areas. For compressor handling flammable gas one extinguisher to be provided within 5 meters of the equipment at each floor level. In buildings fire extinguishers shall be installed in concealed type cabinet combined with hose reel.

Dry chemical powder cartridge type suitable for types A, B and C fires shall be provided in process unit, utilities unit and near transformers. These shall be provided at pumps, compressor handling flammable products and at vessels with a liquid hold up more than 1 m3. These shall be also provided on high-level walkways. Units shall also be provided in buildings.

Wheeled ABC dry chemical powder extinguisher shall be located in fire point shelters only.

CO2 extinguishers shall be used for electric and / or electronic equipment fires such as switchgear houses, substations, instrument equipment shelters, analyzer buildings and laboratory. CO2 extinguishers shall be installed close to electrical and / or electronic equipment with travel distance 6 m maximum. Wheeled Carbon Dioxide extinguishers shall be supplied for substations and boiler areas.

For offices, no water extinguishers shall be provided but only 9 kg dry powder and 5 kg CO2 extinguishers. Water hose reels each containing 11/2”diameter fire hose of maximum length 31 m shall also be installed, connected to the fire water system.


Fire fighting steam


If necessary, utility connections from the low-pressure steam system shall be provided for steam lances with 15 m long electrically earthen hoses. Steam lances should be used to smother small fires caused by leakage from equipment handling flammable products on or above auto-ignition temperature

First aid boxes


One first aid box each shall be installed in each operator shelter, fire point shelter, electrical substation and IES building.

Substations shall be provided with Suitable first aid boxes.



Breathing apparatus


30 min Breathing Apparatus sets shall be located in fluids containing H2S Process, Utility areas, operator shelters, IES, analyzer rooms and SCADA shelter, fire point shelters. Breathing apparatus sets shall be kept inside weatherproof boxes (as per the one). Additional BA (10%) shall be provided in fire station as back up. A breathing air supply for maintenance shall be also provided


Fire blankets


Wall mounted Fire Blankets shall be provided and installed within Process and Utility units at strategic locations.


Fire-fighting vehicles


Fire Fighting vehicles and ambulance shall be provided for new plants as per requirements.


Safety Showers And Eye Washes


Safety Showers and / or Eye Washes shall be provided in chemical handling areas


Fire Training Facility


The fire training facility shall be located with a safety distance of 100 meters from all units.

A branch from the firewater network shall run to the fire training facility. This branch shall be fitted with 2 hydrants and 2 hydrants with top mounted monitors.



Fireproofing


The main objective of fireproofing of steel structures is to prevent the escalation of fires to an unacceptable level providing a temporary protection until full fire-fighting capabilities can be deployed. Judicious application of fireproofing shall delay an eventual collapse of steel structures and allow it to occur gradually depicting visible signs that provide time for isolation of the affected equipment as well as for operating and fire-fighting personnel to evacuate safely. For specific information as to the requirements for fireproofing


Fire Station


Fire station shall be designed as per requirements.

Note: For large processing complexes the addition of satellite or new fire stations shall be considered (based on the minimum response time to the farthest point from the main fire station).


Fire Protection Requirements Per Area


Gas turbines, Emergency generators and compressors enclosures


An automatic CO2 fire suppression system shall be installed to protect the inside of gas turbine,

Emergency generators and flammable gas compressor enclosures for protection against hazardous gas mixtures and fires. Inerting the enclosure by the reduction of oxygen shall suppress and extinguish the fire. The automatic CO2 shall meet the requirements of NFPA 850 and NFPA 12. All equipment shall be UL and / or FM approved or Vendor National approval. CO2 bottles shall be equipped with pressure indicators and with weighing indicator connected to Fire and Gas System. Each system shall comprise a dedicated fire and gas detection and protection system with extensive requirements with respect to detection, visible / audible alarms, logic, delay of agent release, area ventilation etc. The dedicated fire and gas system shall meet the requirements of NFPA 850, 70 and 72.

Gas turbines and compressor sets installed in the open air shall be protected by a fixed-water spray system.


General process areas


Fixed-installed fire-protection and fire-fighting systems Monitors

Fixed-installed, manually adjustable and operated water monitors shall be positioned at strategic points around hazardous areas. For the specification of monitors. Water spray systems or deluge systems, Open automatic water spray systems shall be installed for the protection of the following equipment:

All pumps handling products close to or above their auto-ignition temperature.

Pumps handling C4 and lighter products.

Note:

The pump and a width of 1.5 m around the pump shall be covered by water spray. The water rate directly over the pump shall be approximately 40 dm3 / min / m2 and on the area around the pump 20 dm3 / min / m2.



All compressors handling C4 and lighter products which are not installed in enclosures and cannot be covered by fixed-installed, manually adjustable and operated water monitors. Water rate shall be 40 dm3 / min / m2 of ground surface.

All vessels, columns and exchangers normally holding a liquid volume of C4 and lighter products of more than 5 m3.

Water rate shall be 10.2 dm3 / min / m2 of equipment surface.

Vertical vessels and columns shall be fully sprayed up to a height of approximately 15 m above the potential source of fire, excluding the skirt.

For equipment installed in congested areas where escalation could occur, a spray system shall be provided at the potential source of fire generally pumps with additional protection to cover a resultant spill fire and the facing surface areas of adjacent equipment applying water rates as given above.

Items of equipment containing flammable products which are installed in locations where a chimney effect occurs in the event of a fire or pumps handling flammable products located underneath air-cooled heat exchangers or critical flanged connections. Water rate shall be 20 dm3 /min / m2 of ground surface for pumps and of equipment surface for other items.

Each deluge system shall be fed from two different separated headers and provided with drainage facilities. Deluge valves shall be located at least 15 m away from the protected equipment, protected against radiant heat by a suitable protection wall and against collision by crash barriers painted in fluorescent red and white paint. Each automatic deluge valve system shall be provided with an air reservoir as a back up in case of instrument air failure. It shall be mounted on a skid. Deluge systems spray nozzles shall have blow-off plastic caps. Flushing facility for deluge valve systems shall be provided to prevent salt deposits accumulation and to prevent system piping corrosion. Deluge system shall initiate the local fire alarm. Deluge system activation shall also give alarms as well as indication at both main control room, fire station and automatically start the main pump. Each deluge valve shall be provided with strainer and bypass connections.

Hose reel station


Hose reel stations shall be provided in process units. Two stations shall be positioned within 23 meters (walking distance) from any point within the production facilities area. Hose reel stations shall be equipped with 31 meter of 1-1/2”, 19 mm internal bore, 500 # non-collapsible rubber hose and adjustable flow, combination straight-stream fog type (all brass) nozzles. Reels shall allow hose to be put into service without unwinding the reel. Manifolding including an eductor shall be provided at each station to permit the use of water only or to allow the introduction of foam from a 115 liters stainless steel foam tank. Hose reel stations shall be protected inside weatherproof closed cabinets.



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