1. INTRODUCTION: 1.1 bawa-speci Version 01 CONTENTS 2. PART I ALL ABOUT MIST SYSTEM: 2.1 Halon alternative system 2.2 Water Mist Technology 2.3 - High Pressure / Intermediate Pressure Water Mist 2.4 Extinguishing Principles of Mist system 2.5 Human Safety 2.6 Applications 2.7 Limitations 2.8 Awareness on Water Mist System 2.9 Standards and approvals 3. PART II FIRE EXTINGUISHING / SUPPRESSION SYSTEM USING HIGH PRESSURE / INTERMEDIATE PRESSURE WATER MIST SYSTEM 3.1 Area / Risks are to be protected with 3.2 Classification of Extinguishing System 3.3 Detection System 3.4 Fire Extinguishing System 3.3.1 Design Basis 3.3.2 System Requirement 3.3.3 Data Sheets 3.3.4 Drawings (a) Schematic Diagram for Water Mist System (b) Cylinder arrangement (c) Isometric diagram of distribution pipe with nozzle 3.3.5 Final Inspection and approval 3.5 Maintenance
1. INTRODUCTION: 1.1. bawa-speci Version 01: bawa-speci is developed as a powerful tool for Consultant, Designer, Engineers, End users, Fire Protection Professionals and Fire & Safety Technocrats. This is a simple powerful tool to assist the concerned professionals to write proper specifications in design, supply, erection, testing, commissioning and maintenance of environmentally accepted Halon alternative High Pressure Water Mist Fire Protection System with trade name of High Pressure Water Mist This bawa-speci is divided in to 2 parts. Part I General technical details on Water Mist System Part II Specification and guidance to Responsibilities: This specification is only a guideline for the qualified engineers in Fire Protection field. This is up to the user to take necessary care in incorporating the specific requirement of local authorities if any. 2. PART I ALL ABOUT MIST SYSTEM: 2.1. Halon alternative system: The regulation of Halon 1301 under the Montreal Protocol and its amendments culminated in the phase out of production and use of Halon. This regulation engendered tremendous research and development efforts across the world in a search for replacements and alternatives. Some of the alternatives Extinguishers are 1. Halocarbon 2. Inert gases 3. Water Mist
All chemicals with non-zero ODP are subject to phase out under the Montreal Protocol and its amendments. The following table summarizes environmental impact data for halocarbon alternatives. Note that FC and HFC compounds have zero ozone depletion potential. The HCFC compounds have quite low ODP. Other HCFC compounds are widely used as CFC replacements for refrigerants. Other environmental factors that are potentially important in a regulatory context are global warning potential (GWP) and atmospheric lifetime. GWP is a measure of the contribution of a gas to the so-called greenhouse effect. It is a function of atmospheric lifetime and the ability of the gas to absorb infrared radiation. Table Environmental Factors for Halocarbon Clean Agents Trade Name Designation Formula ODP GWP Atmospheric (100 yr) Lifetime (yr) Halon 1301 Halon 1301 CF 3 Br 16 5800 100 CEA-410 FC-3-1-10 C 4 F 10 0 5500 2600 FM-200 HFC-227ea C 3 F 7 H 0 2050 31 FE-13 HFC-23 CHF 3 0 9000 280 FE-24 HCFC-124 C 2 HCIF 4 0.022 440 7 FE-25 HFC-125 H 2 HF 5 0 3400 41 NAF-S-III HCFC Blend A HCFC-22 82% 0 1600 16 HCFC-123 4.75% 0.05 HCFC-124 4.5% Organic 3 3.75% Some of the presently offered chemicals extinguishing gases do contribute to green house effect. These fire-extinguishing gases are expected to be restricted or even to be prohibited in the foreseeable future as per Kyoto Protocol. 2.2. Water Mist Technology: The technique of Fire suppression / extinguishing with Water Mist has been known already for many years. Due to the technology development, concept of using Water Mist for fire suppression has spread very rapidly.
Because of the many unique advantages, Water Mist is used as an alternative for both gas-extinguishing systems and to Sprinkler systems. For certain hazards which have up to now been covered with Sprinklers, Water Mist represents a better protection because of its more powerful cooling effect and its almost three dimensional expansion. Water Mist extinguishing technology is using very fine water sprays. Very fine water spray can be defined by size of water drop, which should not be more than 1000 μm for DV 90. DV 90 is the volume median diameter that is 90% of the total volume of liquid is in drops of smaller diameter and 10% is in drops of larger diameter. Based on particle size, Mist is classified as Class 1 Water Mist up to 200 μm of water drop size, Class 2 Water Mist up to 400 μm of water drop size and Class 3 Water Mist up to 1000 μm of water drop size. Further Mist extinguishing technology can be broadly classified as High Pressure Water Mist Pressure of 35 bar and above, Intermediate Pressure Water Mist Pressure above 12 bar but less than 35 bar and Low Pressure Water Mist Pressure up to 12 bar. Based on water supply, Water Mist technology can be of limited water supply system. 2.3. High Pressure / Intermediate Pressure Water Mist Halon 1301 was very widely used as Fire extinguishing agent for total flooding application as well as local application. Due to impact on the environment has led to an intense search for Halon replacement for Fire Protection. Various new clean agents are developed to replace Halon 1301. High Pressure / Intermediate Pressure Water Mist Fire Protection is one of the most accepted Halon alternatives for total flooding system and local application system. is the trade name of M/s. bala fire safety Water Mist System. High Pressure / Intermediate Pressure Water Mist Fire Protection meets requirement of NFPA 750 of USA standard and AS 4587-99
of Australian standard and Standard of Halon Alternative Options Committee (HAOC) of India. This system can be used to fight fires of classes A, B and C. Water Mist Systems offer potential benefits for many specialised application. Particularly when available water supplies are limited or when the application of water must be restricted. The system design is supported by version-01. design programme, is environmentally accepted system. This can be used in manned area. Since water is the main extinguishing agent, refilling is very simple and low cost. consists of required cylinder bank based on the size of area. Cylinder bank includes Water cylinders, Nitrogen cylinders, Manifold, Discharge Hose, Pressurization Hoses, Non-return valves, Solenoid actuator, Pressure switch & Bleeder valve. Seamless stainless steel tubes are used for distribution of extinguishing agent up to Nozzles. The special type Nozzles are fixed in the protected area to discharges the water mist during the operation. The System is designed to operate as follows: (a) (b) (c) By totally automatic using Detectors, Control Panel as per the system requirement. Control panel provides suitable signal of 24 V / 12 V DC to actuate solenoid fitted on Nitrogen cylinder. Nitrogen gas will be regulated through high-pressure regulator and used to pressurize water cylinders. Water Mist will be discharged through Discharge Hose, Manifold, distribution pipe and finally nozzle at protected area. By manually electrically. Manual Push Button Station is provided at appropriate place as per system requirement. By operating Manual Push Button Station, Control Panel provides necessary electrical signal to activate solenoid and system operates as explained above. By manually mechanically. By operating manually the knob or lever of solenoid valve assembly, N 2 gas can be discharged and system will operate as explained above. High Pressure / Intermediate Pressure Water Mist System can be supplied with third party inspection like BVQI/LLOYDS. is supported with specification document referred as bawaspeci.
2.4. Extinguishing Principles of Mist system: It is interesting to understand the stay extinguishing technique of the Water Mist System. The Water Mist in the air for more time as its expands almost three dimensionally. In the fire situation, fire source draw the air and subsequently Water Mist also spreads in the direction of the fire source. The splitting of water in to very small droplets reacts on larger surface area and heat of the fire is absorbed. The larger heat absorption capacity is shown while heating the water from 20 to 100 C and transformed in to water steam. The evaporation of water volume increases by 1640 times. This expansion takes place on the spot in direct vicinity of fire source. This explains that Water Mist not only flow in to the direction of fire source but also away from it against the direction of inflowing O 2. The fire source can be housed with vapourized water, which effectively reduces O 2 from 16% to 8% by volume in the immediate vicinity of the fire source. Thus creates Fire Extinguishing or Suppression. 2.5. Human Safety: The capability of Water Mist to reduce the temperature very fast and wash out the flue gases is one of the important protection for the people in the fire area. This makes Water Mist is an ideal choice for area where people are present. During the extinguishing process, rest of the room is maintained with normal O 2 level because reductions of O 2 taking place only in the immediate vicinity of the fire source. 2.6. Applications of the Water Mist System: Water Mist can be used for the following applications as per AS 4587-99 of Australian Standard and Draft Indian Standard on Water Mist. (a) (b) (c) Rooms, vaults, enclosed machines, containers, storage tanks and bins. Flammable liquid storage and processing areas. Engines using flammable fuels.
(d) Computers, data processing equipment and control rooms. (e) Electrical hazards, such as transformers, switches, circuit breakers, and rotating equipment. (f) Electronic equipment, including telecommunications equipment. (g) Cooking equipment using cooking oils and fats. 2.7. Limitations of the Water Mist System: The system shall not be used for direct application to materials that react with water to produce significant amounts of heat or hazardous products. These materials include the following: (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) Reactive metals, such as lithium, sodium, potassium, magnesium, titanium, zirconium, uranium and plutonium etc. Metal alkoxides, such as sodium methoxide, Metal amides, such as sodium amide. Carbides, such as calcium carbide. Halides, such as benzoyl chloride and aluminium chloride. Hydrides, such as lithium aluminium hydride. Oxyhalides, such as phosphorus exybromide. Silanes, such as trichloromethysilance. Sulfides, such as phosphorus pentasulfide. Cyanates, such as methylisocyanate. 2.8. Awareness on Water Mist System: 2.8.1. Global Supplier Water Mist System is being used already globally. However the use of Water Mist System for Fire Protection application is new to Indian Customers. Globally some of the following known manufacturers offering Water Mist System. 1. Hi-Fog Water Mist System by M/s. Marioff Corporation Oy, Finland 2. Micro Mist System by M/s. Fike Corporation, USA 3. Water Mist System by M/s. Chemetron Fire Systems, U.S. 4. Aqua Mist System by M/s. TYCO International Ltd., U.S. 5. Water Mist System by M/s. Acme Fire & Safety Co. Ltd., Canada.
6. In India, Water Mist System i.e. offered by M/s. bala fire safety, Chennai. 2.8.2. Global Installation The following Water Mist Systems are installed globally on various applications. 1. More than 250 Water Mist Systems are already installed and functioning in London Underground sections. 2. Madrid-Metro in Spain installed Water Mist System to protect their Engine room elevators. 3. Vauxhall and Rover Car Manufacturers and Vosper Thornicraft Ltd., U.K. used Water Mist System for their Engine test cell. 4. IBM Computer facilities in U.K. protected with Water Mist System. 5. More than 100 ships are protected with Water Mist System for their various applications. 6. Water Mist System installations are used in Oil Production Platforms for protecting gas turbine in Australia. 2.8.3. Is Water Mist Suitable for Server/Computer and Telecommunication facilities Using water mist has very unique advantage over gaseous system. In a fire situation smoke causes considerable damage to electronic equipment and data. Water mist is the best smoke scrubber. Water Mist system is already used in IBM system facility in UK installed by M/s. Preussag Fire Protection Ltd., And also similar protection at various European countries. Various tests have shown all fires in the void and in cabinets extinguished in less than 3 minutes with negligible water deposit on the floor of the void and no discernible (visible) water deposited in the cabinets or on to the circuit boards. There is no thermal or static shock observed. Normally electronic boards and equipments have protection against moisture and humidity. Therefore mist system will not effect the equipments since very very minimum water quantity is used. National Aeronautics and Space Administration Glenn Research Centre, Cleaveland, Ohio conducted Water Mist Fire Suppression
Experiment. They confirm the application of water mist to protect the following facilities. 1. Ships (Machinery Spaces) 2. Aircraft (Passenger Cabin and Cargo) 3. Spacecraft 4. Libraries, Museums 5. Telecommunication racks 6. Commercial cooking area Based on our question on application of water mist for computer and telecommunication rooms, Dr.Angel Abbud Madrid, Associate Research Professor, Chemical Engineering Dept, Colorodo School of Mines USA has confirmed that the possible application of water mist system for Fire Suppression in Computer and Telecommunications room is based on the results of some tests that have conducted on this type of facilities by several researchers. 2.9. Standards and Approvals : (a) (b) (c) (d) (e) (f) (g) Draft IS Standard AS 4587-99 Australian Standard NFPA 750, USA Cylinders with ISI mark and CCE approval Actuating Solenoid UL Listed. Mist Valve Manufacturer Approval as per design programme Mist Nozzle Manufacturer Approval as per design programme
3. PART II FIRE EXTINGUISHING / SUPPRESSION SYSTEM USING HIGH PRESSURE / INTERMEDIATE PRESSURE WATER MIST SYSTEM 3.1. Area / Risks are to be protected with : 3.1.1. Protection for Commercial Facilities 1. Computer Room 2. Data Processing Equipment Room 3. Multi store building, Underground cellar storage facilities 4. Diesel power generator in under ground cellar 5. Diesel Engine driven Fire Pump Room 6. Telecommunication center 7. Commercial Restaurant Kitchen with cooking equipment 3.1.2. Protection for Industrial Facilities 1. Switch Gear Room 2. Control Room 3. Rotary Equipment 4. Gas Turbines 5. Generators 6. Flammable Liquid Storage 7. Painting Booth 8. Painting Kitchen 9. Printing Machineries 10. Enclosed Machines 11. Engine Room 12. Engine Test Benches 13. Process Liquid Pumping Area / Station 14. Indoor Transformer 15. Cable Gallery 16. Conveyor Protection
3.1.3. General Protection 1. Ship (Machinery Space) 2. Air Craft (Passenger cabin & Cargo) 3. Space Craft 4. Libraries, Museums 3.2. Classification of Extinguishing System 3.2.1. Protection for Commercial Facilities Areas are to be Protected Recommended System Pressure 1. Computer Room High Pressure System 2. Data Processing Equipment Room High Pressure System 3. Multi store building, Underground Intermediate Pressure System cellar storage facilities 4. Diesel power generator in under Intermediate Pressure System ground cellar 5. Diesel Engine driven Fire Pump Room Intermediate Pressure System 6. Telecommunication center Intermediate Pressure System 7. Commercial Restaurant Kitchen with Intermediate Pressure System cooking equipment 3.2.2. Protection for Industrial Facilities Areas are to be Protected Recommended System Pressure 1. Switch Gear Room Intermediate Pressure System 2. Control Room High Pressure System 3. Rotary Equipment Intermediate Pressure System 4. Gas Turbines Intermediate Pressure System 5. Generators Intermediate Pressure System 6. Flammable Liquid Storage Intermediate Pressure System 7. Painting Booth Intermediate Pressure System 8. Painting Kitchen Intermediate Pressure System 9. Printing Machineries Intermediate Pressure System 10. Enclosed Machines Intermediate Pressure System 11. Engine Room Intermediate Pressure System 12. Engine Test Benches Intermediate Pressure System
13. Process Liquid Pumping Area / Intermediate Pressure System Station 14. Indoor Transformer Intermediate Pressure System 15. Cable Gallery Intermediate Pressure System 16. Conveyor Protection Intermediate Pressure System 3.2.3. General Protection Areas are to be Protected Recommended System Pressure 1. Ship (Machinery Space) Intermediate Pressure System 2. Air Craft (Passenger cabin & Cargo) Intermediate Pressure System 3. Space Craft Intermediate Pressure System 4. Libraries, Museums Intermediate Pressure System 3.3. Detection System Occurrence of Fire can be detected at the very early stage itself by using i) Smoke Detectors ii) Heat Detectors iii) Spark / Flame Detectors Conventional Detection System and Addressable analogue detection and alarm systems are presently used. While users have wide range and types of products, they have to choose correct type of detector and control panel based on application, cost, after sales service. Very early warning detectors like laser type are also available now. Electrical requirement of water mist system is 500 ma at 24 V DC for each solenoid valve. Water mist system is not essentially required cross zone configuration and delayed discharge. Therefore standard fire detection and alarm panel can be used to discharge mist system. However when mist system is design to protect multi areas with main & stand-by, necessary control logic are to be incorporated in the extinguishing panel. Fire detection and Alarm System shall be confirm the following standards (a) IS-2189-99 Edition, Code of practice for selection, installation and maintenance of automatic fire detection and alarm system.
(b) (c) TAC Fire Alarm System Manual NFPA-72E 3.4. Fire Extinguishing System 3.4.1. Design Basis Water mist system is to be designed based on Indian Standard, AS- 4587-99, Australian Standard, NFPA-750, USA and design programme 3.4.2. System Requirement Nature of area or risk to be protected shall be described properly by provider all relevant information. Relevant information may be 1. Type of equipments 2. Flash point of Flammable liquids 3. Material of construction of major equipments 4. Continuous operation or intermediate operation. 5. 24 hour manned area or only on general shift 6. Partially manned area 7. Totally closed enclosure or partially closing is possible 8. Open area application 9. Details on storage materials 10. Height of Storage materials 11. Size of area (Height, breath & width) 12. False Ceiling details 13. False Floor details Based on the above information High Pressure or Intermediate Pressure Water Mist System are to be considered as per the guidelines of clause 4.2 Using arrived. design programme, bill of quantity will be
Data sheet are to be prepared as per clause 4.4.3. Pressure drop calculation as per design programme The following details are to be prepared. 1. Cylinder bank arrangement 2. P & I or Schematic diagram 3. Isometric drawing 4. Piping Layout of Water Mist System Consists of following main items. 1. N 2 Cylinder fitted with High Pressure Regulator, actuation valve with 24 V DC Solenoid and other accessories filled with 7 m 3 N2 gas at 140 bar pressure. 2. Cylinder with mist valve bwm V01 filled with 45 Ltrs Portable H 2 O without pressure 3. Cylinder bank fabricated with 40 Sq.mm tube of powder coating finishing complete with Seamless Stainless Steel Header, Non- Return Valve, Pressure Switch, High Pressure S.S wire braided Discharge Hose, High Pressure S.S wire braided pressurizing hose & bleeder valve 4. High Pressure Water Mist nozzle bwm-n01 & N02 series 5. Seamless Sch.40 S.S Pipe & Fitting The System is designed to operate as follows a. By totally automatic using Detectors, Control Panel as per the system requirement. Control panel provides suitable signal of 24 V / 12 V DC to actuate solenoid fitted on Nitrogen cylinder. Nitrogen gas will be regulated through high-pressure regulator and used to pressurize water cylinders. Water Mist will be discharged through Discharge Hose, Manifold, distribution pipe and finally nozzle at protected area. b. By manually electrically. Manual Push Button Station is provided at appropriate place as per system requirement. By operating Manual Push Button Station, Control Panel provides necessary electrical signal to activate solenoid and system operates as explained above.
c. By manually mechanically. By operating manually the knob or lever of solenoid valve assembly, N 2 gas can be discharged and system will operate as explained above. 3.4.3. Technical Data Sheets 1.0 Type of System : bala-wa-mist High Pressure / Intermediate Pressure Water Mist System 2.0 Type of Application : Total Compartment Flooding / Local Application 3.0 Nominal System Working Pressure : 40 bar / 25 bar 4.0 Design Code / Standard to which : 1. Draft IS Standard design / manufacture/ testing confirm 2. AS 4587-99 Australian Standard 3. NFPA-750, USA 5.0 System designed to protect the : Total Risk largest or total risk 6.0 Classification of Fire : Class A, Class B, Class C and combination of any two or all together 7.0 Discharge Time : 10 minutes / 15 minutes / 20 minutes 8.0 Initial / Extended Discharge : Required / Not Required 9.0 Design Density : Refer bala-wa-mist design programme Version-01 10.0 No.of Nitrogen Cylinder, : Refer bala-wa-mist design 7 Cu.m Capacity, 140 bar pressure programme Version-01 11.0 No.of H2O Cylinder, : Refer bala-wa-mist design 45 Ltrs Capacity, programme Version-01 12.0 No.of Mist Nozzle, : Refer bala-wa-mist design programme version-01 13.0 Nozzle Coverage : Total Flooding 25 Cu.m 30 Cu.m Local Application upto 6 Sq.m 14.0 Nozzle Height : 5.5m Maximum 15.0 Distribution pipe sizing : 12NB 50NB 16.0 Distribution pipe length : 150 Mtr Maximum 17.0 Cylinder Bank Size : 18.0 Mist System Cylinder Details a. Manufacturer : EKC / MKCL b. Design Code : IS : 7285 c. Capacity : 46.7 Ltrs Water Capacity d. H 2 O Stored Capacity : 45 Ltrs.
e. N 2 Gas Holding Capacity : 7 Cu.m f. Approval : ISI marked & CCE approved g. Working Pressure : 150 bar h. Testing Pressure : 250 bar i. Dimension of Cylinder : 232 mm(dia) x 1340 mm (Ht) x 5.5 mm 19.0 Pipes Valves and fittings a. Material of Construction 1. Pipes : SS 304, Seamless Sch.40 2. Fittings : SS 304, Forged Fittings 3. Valves (Non Return) : Brass / SS b. Type of Joints : Welded / Threaded c. Hydraulic Test Pressure of Header : 60 bar d. Directional valve 1. Make : M/s. Bala Fire Safety 2. Model : bwm-dv01 series 3. Type : Pneumatic Operated 4. Material of Construction : SS 5. Test Pressure : 60 bar e. Discharge Nozzle 1. Make : M/s. Bala Fire Safety 2. Model : bwm-n01 & N02 Series 3. Type : Threaded Type 4. Material of Construction : Brass / SS 5. Minimum Working Pressure : 35 bar / 20 bar. e. Cylinder Valve 1. Make : M/s. Bala Fire Safety 2. Model : bwm-v01 series 3. Type : Pneumatic Operated 4. Material of Construction : Brass 5. Working Pressure : 40 bar / 25 bar. f. Pressure Regulator 1. Service Pressure : 230 bar / 250 bar 2. Working Outlet Pressure : 40 bar / 25 bar. 3. Gas Service : Nitrogen g. Solenoid Valve 1. Max. Working Pressure : 100 bar 2. Operating Voltage : 24 V DC 3. Approval : UL Listed g. High Pressure Hoses
1. Max. Working Pressure : 140 bar 2. Test Pressure : 280 bar 3. Material of Construction : Inner rubber tube with Double wire braided and outer rubber cover with SS304 wire braiding.
3.4.5. Inspection and Approval 1. Visual & Verification of materials as per approved data sheet 2. Verification of Installation as per the approved drawing. 3. Actuation of Mist System Test Partially or Fully or verification of similar test report for similar test conducted by the installer. 4. Approval based on the accepted approval procedure 3.5. Maintenance (a) (b) System has to be checked semi annually by competent person. And also as per approved maintenance procedure.