20201026-Fire Fighting -ENG.Iyad Al-Alem

STANDARDS & REFERENCES  The most common standards used in this field is:  Jordanian fire Fighting Systems Code.  NFPA 13: Standard for the Installation of Sprinkler Systems.

Classification of Fire Hazards for Sprinkler Design :  Occupancies shall be classified as four classes based on its use and content of materials stored.  Light Hazard: The areas and occupancies which are used for non-industrial uses and contains low quantity and less combustible materials which are expected to release less heat release rates during fire condition shall be classified as light hazard occupancies.  Ordinary Hazard: The areas and occupancies used for processing and handling of mainly ordinary combustible materials unlikely to develop intensely burning fires in the initial stages shall be classified as ordinary hazard occupancies. Ordinary Occupancies shall be further sub classified in to two groups.

Classification of Fire Hazards for Sprinkler Design :  Extra High Hazard: The areas and occupancies used for processing and handling abnormal fire loads, likely to produce exceptionally intense fires with high rates of heat release and with high storage heights. Extra high hazard occupancies shall be further classified in to two groups.  Special / Storage Hazard : The areas and occupancies used for miscellaneous storage purposes having storage height greater than 3.6 meters shall be classified in to storage hazard occupancies.



General  Sprinkler heads shall be installed throughout the building as per the design requirements based on the type of hazard occupancy classifications in all office buildings.  Sprinklers shall be installed in such a way that its maximum protection area does not exceeding the limit according to the hazard occupancy.  Sprinkler shall be installed based on its construction type and performance characteristics without obstructing its discharge pattern. See Figure for the discharge pattern for standard upright or pendent sprinkler.





Determination of Protection Area of Coverage.  The protection area of coverage of the sprinkler shall be established by multiplying the S dimension by the L dimension, as follows:  As = S × L

Maximum Distance from Walls.  Maximum Distance from Walls.  The distance from sprinklers to walls shall not exceed one-half of the allowable maximum distance between sprinklers.  The distance from the wall to the sprinkler shall be measured perpendicular to the wall.  The distance from the wall to the sprinkler shall be measured to the wall behind furniture, such as wardrobes, cabinets, and trophy cases.  The distance from the wall to the sprinkler shall be measured to the wall when sprinklers are spaced near windows and no additional floor space is created.

Sprinklers shall be permitted to be located not more than 9 ft (2.7 m) from any single wall.  Small Room. A compartment of light hazard occupancy classification having unobstructed construction and a floor area not exceeding 800 ft2 (74 m2).

Upright Sprinkler Heads  Upright sprinkler heads shall be installed in such a way that its deflector is facing upright position only with the frame arms parallel to the branch line to minimize the obstruction of its discharge pattern.  Upright sprinklers shall be installed where there is no false ceiling, such as car park, stores, plant rooms, concealed spaces above false ceiling areas etc.  The distance between upright sprinkler deflector to the ceiling shall be not less 25mm and shall be not more than 300 mm.  Where situation does not permits to locate the sprinkler head within 300mm from the ceiling and exceeds 300mm, shall be fitted with a deflector plate made of stainless steel having diameter not less 200mm shall be installed attaching to the deflector.  Upright sprinkler protective caps and straps shall be removed immediately after the commissioning of the sprinkler system.  Upright sprinklers shall be fitted with a protective guard where there is possibilities for accidental damage of sprinkler bulbs.  The minimum distance between the sprinkler to the adjacent sprinkler shall be not less than 1.8 meters.

Upright Sprinkler Heads  The maximum distance between the standard upright sprinkler to the adjacent standard sprinkler shall be not more than 4.6 meters.  The minimum distance between a upright sprinkler to a wall shall be not less than 100mm.  The maximum distance between a standard upright sprinkler to a wall shall be not more than 2.3 meters or ½ of the spacing between the sprinkler.  There should not be any continuous or non-continuous obstructions such as columns, beams, truss webs and chords, pipes, ducts, and other fixtures that could prevent discharge pattern below the sprinkler head for less than or equal to 500 mm.  Sprinklers shall be installed under fixed obstructions over 1.2 m wide such as ducts, cable trays, decks, open grate floorings etc.  The minimum clearance between top of storage to the sprinkler head shall be not less than 500mm and shall be 1000mm in special situations for special sprinklers such as ESFR sprinklers.

Upright Sprinkler Heads  Sprinklers under glass or plastic skylights exposed to the direct rays of the sun shall be of the intermediate-temperature classification.  Where there is a vertical change in ceiling elevation within the area of coverage of the sprinkler creating a distance of more than 900 mm between the upper ceiling and the sprinkler deflector, a vertical plane extending down from the ceiling at the change in elevation shall be considered a wall for the purpose of sprinkler spacing.  Sprinklers shall be located so as to minimize obstructions to discharge or additional sprinklers shall be provided to ensure adequate coverage of the hazard.  Sprinklers shall be permitted to be spaced on opposite sides of obstructions not exceeding 1.2 m in width, provided the distance from the center line of the obstruction to the sprinklers does not exceed one-half the allowable distance permitted between sprinklers.

Positioning of Standard upright sprinklers to avoid obstruction of discharge pattern  Under obstructed construction, the sprinklers shall be permitted to install as per the Table to avoid obstructions of discharge pattern of an upright sprinkler.

Pendent Sprinkler Heads  Pendent sprinkler heads shall be installed in such a way that its deflector is facing downwards pendent position only with the frame arms parallel to the branch line to minimize the obstruction of its discharge pattern.  Pendent sprinkler protective caps and straps shall be removed immediately after the commissioning of the sprinkler system.  Pendent sprinklers shall be fitted with a protective guard where there is possibilities for accidental damage of sprinkler bulbs.  The minimum distance between the sprinkler to the adjacent sprinkler shall be not less than 1.8 m.  The maximum distance between the standard pendent sprinkler to the adjacent standard sprinkler shall be not more than 4.6 meters.  The minimum distance between a pendent sprinkler to a wall shall be not less than 100mm.

Pendent Sprinkler Heads  The maximum distance between a standard pendent sprinkler to a wall shall be not more than 2.3 meters or ½ of the spacing between the sprinkler.  Under obstructed construction, the sprinkler shall be installed in each bay of obstructed construction with the sprinkler deflector located not less than 25 mm to not more than 300mm from the ceiling.  Sprinklers shall be installed under fixed obstructions over 1.2 m wide such as ducts, cable trays, decks, open grate floorings etc.  The minimum clearance between top of storage to the sprinkler head shall be not less than 500mm and shall be 1000mm in special situations for special sprinklers such as ESFR & ELO sprinklers.  Sprinklers under glass or plastic skylights exposed to the direct rays of the sun shall be of the intermediate-temperature classification.

Positioning of Standard Pendent sprinklers to avoid obstruction of discharge pattern  Under obstructed construction, the sprinklers shall be permitted to install as per the Table o avoid obstructions of discharge pattern of a pendent sprinkler.

Recessed / Concealed Pendent Sprinkler Heads  Recessed or Concealed type Pendent sprinkler heads shall be installed in such a way that its deflector is facing downwards pendent position only.  Quick / fast response type sprinklers shall be installed in the light hazard areas.  The recessed / concealed pendent sprinklers shall be installed as per the installation guidelines recommended by the original equipment manufacturer.  A listed & approved type flexible drop pipes shall be used for extending the sprinkler drop pipe from the branch pipe to the sprinkler along with approved ceiling support fittings and hardware.

Sidewall Sprinkler Heads  Sidewall sprinkler heads shall be installed along a wall side, or side of a beam or beneath the flat smooth ceiling where upright or pendent sprinklers with open piping may not be desirable due to aesthetics issues.  Sidewall sprinklers shall be installed such that its deflectors are aligned parallel to the ceiling or roof.  Sidewall sprinkler shall be installed in the ramps, for the protection of any office or room where there is no false ceiling and opened piping is not desirable due to aesthetic point.  Quick / fast response type sprinklers shall be installed in the light hazard areas.  Sidewall sprinkler protective caps and straps shall be removed immediately after the commissioning of the sprinkler system.

Sidewall Sprinkler Heads  Sidewall sprinklers shall be fitted with a protective guard where there is possibilities for accidental damage of sprinkler bulbs.  The distance between side wall sprinkler deflector to the ceiling shall be not less 100mm and shall be not more than 150 mm. However in non combustible ceiling areas the distance between side wall sprinkler deflector to the ceiling shall be permitted to be 150mm to 300mm and 300mm to 450 mm if the sprinklers are listed for such use as per original equipment manufacturers technical data sheets.  Where soffits used for the installation of sidewall sprinklers exceed 203 mm in width or projection from the wall, additional sprinklers shall be installed below the soffit.  The minimum distance between the sprinkler to the adjacent sprinkler shall be not less than 1.8 m.

Sidewall Sprinkler Heads  In light hazard occupancies, the maximum distance between the standard sidewall sprinkler to the adjacent standard sprinkler shall be not more than 4.25 m. and the room width shall be not more than 3.6 m.  Where the extended coverage sidewall sprinklers are used, the maximum spacing between sprinklers along the wall and room width shall be not more than its approval listing as per the Original equipment manufacturers technical data sheet.  In ordinary hazard occupancies, the maximum distance between the standard sidewall sprinkler to the adjacent standard sprinkler shall be not more than 3.0 m. and the room width shall be not more than 3.0 m.  The minimum distance between a sidewall sprinkler to a wall shall be not less than 100mm.  The maximum distance between a standard sidewall sprinkler to a wall shall be not more than 2.125 m. in light hazard and shall be not more than 1.5 m. in ordinary hazard or ½ of the spacing between the sprinkler.

Sidewall Sprinkler Heads  There should not be any continuous or non-continuous obstructions such as columns, beams, truss webs and chords, pipes, ducts, and other fixtures that could prevent discharge pattern below the sprinkler head for less than or equal to 500 mm.  Sprinklers shall be installed under fixed obstructions over 1.2 m wide such as ducts, cable trays, decks, open grate floorings etc.  The minimum clearance between top of storage to the sidewall sprinkler head shall be not less than 500mm.  Sidewall sprinklers under glass or plastic skylights exposed to the direct rays of the sun shall be of the intermediate-temperature classification.  Sidewall sprinklers shall be located so as to minimize obstructions to discharge or additional sprinklers shall be provided to ensure adequate coverage of the hazard.  Sidewall sprinklers shall be installed no closer than 1.2 m. from light fixtures or similar obstructions.

Positioning of Standard sidewall Sprinklers to Avoid Obstructions

Obstructions projecting from the same wall as the one on which the sidewall sprinkler is mounted shall be in accordance with Table and Figure shown below.

Sprinklers shall be positioned away from obstructions a minimum distance of three times the maximum dimension of the obstruction (e.g., structural members, pipe, columns, and fixtures). The maximum clear distance required shall be 609 mm in accordance with Figure below.

The distance from sprinklers to privacy curtains, free standing partitions, room dividers, and similar obstructions in light hazard occupancies shall be in accordance with Table and Figure shown below.

Obstructions to Sprinkler Discharge Pattern Development for sidewall sprinklers Sprinklers shall be positioned away from obstructions a minimum distance of three times the maximum dimension of the obstruction (e.g., truss webs and chords, pipe, columns, and fixtures). The maximum clear distance required shall be 609 mm and shall be positioned in accordance with Figure below where obstructions are present.

Suspended or Floor-Mounted Vertical Obstructions for sidewall sprinklers  The distance from sidewall sprinklers to privacy curtains, free- standing partitions, room dividers, and similar obstructions in light hazard occupancies shall be in accordance with Table and Figure 9 shown below.

Example of Shadow Area.

Concealed Spaces  Sprinklers shall be provided in concealed spaces (for example, suspended ceiling, raised floor and behind wall panels) where there are combustibles and services like mechanical ducts, fans, electrical cables and components.  The depth of the concealed space (suspended ceiling and raised floor) shall not be less than 800mm to accommodate installation of sprinkler pipes.  Sprinklers in concealed spaces can be exempted if the concealed space is fire compartmented and that the concealed spaces of egress corridors and passageways are fire compartmented from the concealed spaces of other parts of the floor.

Minimum spacing between sprinkler to the heat source The minimum distance between the heat source to the sprinklers shall be not less than shown in below table.



5 Fire Fighting Systems CALCULATIONS

STANDARDS & REFERENCES  The most common standards used in this field is:  Jordanian fire Fighting Systems Code.  NFPA 13: Standard for the Installation of Sprinkler Systems.

Sprinkler Zone Limitations  The maximum area of any single sprinkler zone in a floor shall be not more than the floor area specified below. The water supply to the sprinklers supplied by any one sprinkler system riser or combined system riser shall be not more than the specified maximum floor area.  Where the floor area exceeds the limit as specified below, an additional water supply risers shall be proposed for every maximum sprinkler zone in each floor complete with sprinkler Alarm check Valve (ACV) assembly and riser isolation valve.  In addition, a floor zone control valve (ZCV) assembly shall be proposed at every floor where the tapping is taken from the sprinkler riser.  Alarm Check Valves (ACV) and Floor Zone Control Valves (ZCV) shall be located inside stair enclosure at a higher level than required ‘Headroom’ for the stairs.

FIRE SPRINKLERS SYSTEM

Sprinkler Operating Pressure and Pipe Sizes: Sprinkler Operating Pressure:  The minimum operating pressure of any sprinkler for determining the water supply requirements shall be not less than 0.5 bar (7 PSI) in the light hazard occupancy and 1.0 bar (14.5 PSI) in the ordinary hazard occupancies.  The maximum operating pressure in a sprinkler system shall not be more than 12 bar.  Where higher operating pressure is used for the sprinkler system, all the sprinklers, pipes and fittings shall be rated for the higher operating pressure, however the operating pressure shall not be more than 16 bar in any case. Pipe Sizes:  The minimum pipe sizes shall be determined according to the hydraulic calculations. However, the minimum pipe sizes shall be not less than the diameters specified in the Table below.  However the number of sprinklers fed by the pipes having 65 mm diameter and above in a sprinkler zone may be permitted to increase subject to the submission of acceptable computerized listed hydraulic calculations according to the area protection limitations as specified.

Pipe Schedules Method :

Pipe Schedules Method :

Pipe Schedules Method :

Hydraulic Calculations Method  Computerized Hydraulic calculations shall be performed to determine the fire water demand, pressure and pipe sizes required for a sprinkler system installed in all types of occupancies.  The hydraulic calculation shall be performed using the Civil Defense listed and approved software. Following criteria shall be used for Hydraulic calculations.  Sprinkler system that is protecting an occupancy hazard that requires greatest water demand situated any where within the occupancy for the design density of discharge according to the occupancy classification.  Sprinkler system that is protecting an occupancy hazard that is located hydraulically farthest point from the source of fire water supply system within the occupancy for the design density of discharge according to the occupancy classification.  Sprinkler system that is protecting an occupancy hazard that is located hydraulically topmost point from the source of fire water supply system within the occupancy for the design density of discharge according to the occupancy classification.  The fire water source shall be selected based on the above criteria, whichever is the greater requirement.

Sprinkler Design Density & Water Supply Requirements  The minimum required design density of water discharge over the protected surface area shall be determined based on the occupancy and hazard classification.  However, If the fire water supply is combined for both sprinkler and stand pipe wet riser system, the fire water demand shall be established as follows:  In the buildings fully protected by an automatic sprinkler system, the fire water demand established for the wet riser system is permitted to serve sprinkler system without adding additional water demand in it.  If the wet riser system demand calculated exceeds the sprinkler system demand including the hose stream allowance, the larger of the two demand value shall be proposed depending on the hazard.

Water Demand Requirements Density/Area Curves.  The water supply for sprinklers only shall be determined from the density/area curves of Figure below.

Water Demand Requirements Density/Area Curves.

Water Demand Requirements  The minimum water demand requirements for a sprinkler system shall be determined by adding the hose stream allowance to the water demand for sprinklers.  The hose stream allowance and water specified in table 11.2.3.1.2.  The minimum water supply shall be available for the minimum duration specified in Table 11.2.3.1.2.



Classification of Commodities.