20201026-Fire Fighting -ENG.Iyad Al-Alem

DEFINITION  Foam is produced by mixing a foam concentrate with water at the appropriate concentration, and then aerating and agitating the solution to form the bubble structure.  The process of producing and applying fire-fighting air-foams to hazards requires three separate operations, each of which consumes energy:  a. The proportioning process;  b. The foam generation phase; or  c. The distribution method.  Foam agent can be discharged through various arrangement of systems such as foam-water sprinkler systems, foam-water deluge spray systems, foam-pouring system and foam monitor systems etc.

COMPONENTS  Fire pumps, controller, foam concentrate pumps, fire water tank, foam concentrate bladder tank, foam proportioning system, pipes, fittings, sprinklers/ spray nozzles, isolation valves, deluge valve, pressure gauge, flow switch, test connection, drains, breeching inlet and signs.  All the components of foam systems including the used water shall be compatible with the foam concentrate and foam solution and listed and approved by Civil Defense.  All foam solutions and type of systems applied to hazard shall be as per the manufacturer’s specifications and Material Safety Data Sheet.  The System components shall be rated for the maximum working pressure to which they are exposed, but not less than 12.1bar (175psi).

COMPONENTS: FOAM CONCENTRATE  Foam concentrates shall be from single manufacturer and single composition. Foam concentrates from different manufacturers, or different brands of the same manufacturer shall not be mixed.  Storage tanks material, methods, storage temperature and other specifications shall be as per the manufacturer’s instructions.  Water-soluble and certain flammable and combustible liquids and polar solvents that are destructive to nonalcoholic-resistant foams shall require the use of alcohol- resistant foams.

COMPONENTS: FOAM SYSTEM LOCATION  FOAM SYSTEM LOCATION: Foam equipment, proportioner , pumps, control valves shall be as close to hazard they are protecting as possible, without compromising the safety of the equipment and of the personnel operating such systems.  FOAM STRAINERS Civil Defense listed strainers, shall be installed, so as to be accessible for cleaning and flushing while maintaining the system discharge during activation.  TEST CONNECTIONS System test connections shall be sized to accommodate both the low flow of the proportioner and the maximum anticipated flow through the proportioner.

LOW EXPANSION FOAM DESIGN CRITERIA  Design criteria for above the surface application with fixed foam discharge outlet for fixed-roof storage tanks containing hydrocarbons shall comply with following Tables .

FOAM WATER DELUGE SYSTEM  The system piping shall be hydraulically designed to obtain a  reasonably uniform foam and water distribution and to allow for the loss of head in water supply piping.  An automatic fire detection in compliance with NFPA 72.  A minimum of 3% foam-water solution shall be discharged.  A piping carrying foam solution shall be sized as if carrying plain water.  The foam Water Deluge System shall have provision for manual operation.

Typical Foam Water Deluge System for Flammable Liquid Storage

Foam Hand line and Monitor for Fixed Roof Hydrocarbon Tanks

Typical fixed foam monitor system for diked area

7 Fire Fighting systems GAS EXTINGUISHING SYSTEM



STANDARDS & REFERENCES  The most common standards used in this field are:  Jordanian Fire Fighting Systems code.  NFPA 2001: Clean Agent Fire Extinguishing Systems.

Gas Based Fire Protection Systems  This standard contains minimum requirements for total flooding clean agent fire extinguishing systems.  Gas extinguishing technology is based mainly on the principle of removing oxygen. By introducing a gaseous extinguishing agent into the room's atmosphere the oxygen content is reduced to the point where the combustion process is halted.  The gas extinguishing process uses either inert or chemical gases. This technique and mechanism using various gases and chemicals such as Clean Agents, CO2, Dry Chemical and Wet Chemical agents and their fire extinguishing properties to fight and extinguish fires are called Gas and Chemical based Fire Protection Systems.

Introduction  Generally it is possible to protect valuable goods in data centers, control rooms, server rooms, electrical rooms, BMS rooms, Telephone Rooms, archives and storages with fire prevention or fire suppression systems.  The actual design of these gas suppression systems shall be based on Civil Defense approved Manufacturer’s recommendations, guidelines and calculations through approved software.  The design, installation, service, and maintenance of clean agent systems shall be performed by those skilled in clean agent fire extinguishing system technology.

Advantages of gas extinguishing technology  Protection of facility and fittings without water damage .  Extinguishing gases are non-conducting .  No danger to personnel using electrical plant or machinery .  No danger of short circuits either during or after the extinguishing process. Ideal Applications:  BMS Rooms  IT Data Center  Electrical Rooms  Museums  LV Rooms  Galleries  Electronic Equipment Rooms  Telecommunication Rooms  Server Rooms

Use and Limitations.  Clean agents shall not be used on fires involving the following materials unless they have been tested to the satisfaction of the authority having jurisdiction:  Certain chemicals or mixtures of chemicals, such as cellulose nitrate and gunpowder, which are capable of rapid oxidation in the absence of air.  Reactive metals such as lithium, sodium, potassium, magnesium, titanium, zirconium, uranium, and plutonium.  Metal hydrides.  Chemicals capable of undergoing auto thermal decomposition, such as certain organic peroxides and hydrazine.

Safety Requirements.  Provision of adequate aisle ways and routes of exit, and procedures to keep them clear at all times.  Provision of emergency lighting and directional signs as necessary to ensure quick, safe evacuation.  Provision of alarms within such areas that will operate immediately upon detection of the fire.  Provision of only outward-swinging, self-closing doors at exits from hazardous areas and, where such doors are latched, provision of panic hardware.  Provision of continuous alarms at entrances to such areas until the atmosphere has been restored to normal.  Provision of warning and instruction signs at entrances to and inside such areas.  Provision for the prompt discovery and rescue of persons rendered unconscious in such areas.  Provision of instruction and drills for all personnel within or in the vicinity of such areas.  Provision of means for prompt ventilation of such areas. Forced ventilation will often be necessary.

System Components:

1. Agent Supply (Halogenated Gases Agent)

1. Agent Supply (Inert Gases Agent)

2. Agent Storage Containers Storage Container Arrangement.  Storage containers and accessories shall be located and arranged so that inspection, testing, recharging, and other maintenance activities are facilitated and interruption of protection is held to a minimum.  Storage containers shall be located as close as possible to or within the hazard or hazards they protect.  Agent storage containers shall not be located where they can be rendered inoperable or unreliable due to mechanical damage or exposure to chemicals or harsh weather conditions or by any other foreseeable cause. Where container exposure to such conditions is unavoidable, then suitable enclosures or protective measures shall be employed.  Storage containers shall be securely installed and secured according to the manufacturer’s listed installation manual and in a manner that provides for convenient individual servicing or content weighing.  Where storage containers are connected to a manifold, automatic means, such as a check valve, shall be provided to prevent agent loss and to ensure personnel safety if the system is operated when any containers are removed for maintenance.

3. Distribution.  Pipes :  Pipe shall be noncombustible material  The minimum design pressure for the piping shall be adjusted to the maximum pressure in the agent container at maximum temperature.  Valves.  All valves shall be listed or approved for the intended use.  All gaskets, o-rings, sealants, and other valve components shall be constructed of materials that are compatible with the agent. Valves shall be protected against mechanical, chemical, or other damage.  Special corrosion-resistant materials or coatings shall be used in severely corrosive atmospheres.

3. Distribution.  Discharge Nozzles.  Discharge nozzles shall be listed for the intended use. Listing criteria shall include flow characteristics, area coverage, height limits, and minimum pressures. Discharge orifices and discharge orifice plates and inserts shall be of a material that is corrosion resistant to the agent used and the atmosphere in the intended application.  Special corrosion-resistant materials or coatings shall be required in severely corrosive atmospheres.  Discharge nozzles shall be permanently marked to identify the manufacturer as well as the type and size of the orifice.

4. Detection, Actuation, Alarm, and Control Systems.  Automatic detection and automatic actuation shall be used.  A means of manual release of the system shall be provided. Manual release shall be accomplished by a mechanical manual release.  Time delays shall be used only for personnel evacuation or to prepare the hazard area for discharge.

SEQUENCE OF OPERATION  A) ACTIVATION OF ANY ONE OF THE DETECTOR IN EITHER CIRCUIT WILL CAUSE  Alarm indication on FACP.  Alarm bell will ring.  Fire signal to main fire alarm panel.

SEQUENCE OF OPERATION  B) SIMULTANEOUS ACTIVATION OF A SECOND DETECTOR IN THE OTHER CIRCUIT WILL CAUSE  Pre-discharge indication on FACP.  Strobe horn will activate.  Starts countdown of set time delay. (Not to exceed 60 seconds)  Signal to close Fire damper / AC unit  Signal to close the room entrance door.

SEQUENCE OF OPERATION C) AT THE END OF SET TIME DELAY.  Release indication on the panel.  Activates Impulse release module which intern gives signal to IVO to electrical or manual activate the impulse valve clean agent container by providing the force required to extend a piston that will open the rupture disc, allowing the agent to be released from the container.  Warning light on the entrance of the hazard.

SEQUENCE OF OPERATION  MANUAL RELEASE OPERATION Activation of manual release switch will cause all operation A,B&C above without any time delay.  ABORT SWITCH OPERATION If the manual abort switch is activated in pre discharge period  Abort indication on Panel.  Release of gas hold till the switch is deactivated.  After the abort is deactivate countdown will start From the initial time and then gas will release.

Design Concentration Requirements:

Total Flooding Quantity.

Total Flooding Quantity.

Total Flooding Quantity:

Example:





6 Fire Fighting systems FIRE PUMP SET



STANDARDS & REFERENCES  The most common standards used in this field is:  Jordanian fire Fighting Systems Code.  NFPA 20: Standard for the Installation of Stationary Pumps for Fire Protection.

General  The below mentioned criteria’s shall be applicable to centrifugal single – stage and multistage pumps of horizontal or vertical shaft design and positive displacement pumps of the horizontal or vertical shaft design which are limited and intended for fire protection system only:  The fire pump unit, consisting of a pump, driver, controller and fittings shall perform in compliance with local code and NFPA 20 standard as an entire unit when installed or when components have been replaced. The selected fire pump is required to be verified with the listing before application.  All the materials used in pump construction shall be tolerance dependent and selected based on the corrosion potential of the environment, fluids used and operational conditions. Engines shall have a nameplate indicating the listed horsepower rating available to drive the pump.

Certification of Fire Pumps  Each pump, driver, controlling equipment, power supply and arrangement and liquid supply shall be tested and certified by a listed laboratory approved by the Civil Defense Authority.  All the equipment, materials or services shall be included in a listing published for fire pump service by a nationally recognized testing laboratory.  A single entity should be designated as having unit responsibility for the pump driver, controller, transfer switch equipment and accessories.  Installation personnel shall be qualified or shall be supervised by persons who are qualified in the installation, inspection and testing of fire protection systems.

Fire pump location and arrangement  The proposed fire pump set for any water based suppression system including fire hydrants shall consists each of the following:  Main Electric Pump  Standby Diesel driven Pump  Electric Jockey Pump  Two electrical pumps can be used, one as duty and another as standby. The power supply for the 2 electrical pumps shall reliable and be independent of each other.

Fire pump location and arrangement  Fire Pumps shall be located at the lowest level of the building pumping upwards. Fire pumps at levels higher than the lowest level of the building with water supply feeding downwards is not allowed.  Pumps shall have minimum flow and pressure according to the hydraulic calculation to supply fire water to sprinklers system, landing valves and hydrants.  A common fire pump set is acceptable to feed both sprinkler and wet riser system. In such case, the fire pump set capacity shall be not less than the highest fire demand calculated.



TYPES OF FIRE PUMPS  Fire Pump Unit: An assembled unit consisting of a fire pump, driver, controller, and accessories.  Centrifugal Pump: A pump in which the pressure is developed principally by the action of centrifugal force.  In-Line Pump. A centrifugal pump whose drive unit is supported by the pump having its suction and discharge flanges on approximately the same centerline.

TYPES OF FIRE PUMPS  End Suction Pump: A single suction pump having its suction nozzle on the opposite side of the casing from the stuffing box and having the face of the suction nozzle perpendicular to the longitudinal axis of the shaft.  Horizontal Split-Case Pump. A centrifugal pump characterized by a housing that is split parallel to the shaft.

Vertical Line shaft Turbine Pump.  A vertical shaft centrifugal pump with rotating impeller or impellers and with discharge from the pumping element coaxial with the shaft.  The pumping element is suspended by the conductor system, which encloses a system of vertical shafting used to transmit power to the impellers, the prime mover being external to the flow stream.

Vertical Line shaft Turbine Pump.



Vertical Line shaft Turbine Pump.

Horizontal Split-Case Fire Pump Installation with Water Supply Under a Positive Head.