1.1 Minimax's Econ Aqua low pressure mist system Low pressure water mist extinguishing system based on sprinkler technology with particularly low consumption of water, thus providing great benefits for building owners and operators. The EconAqua system reduces water consumption by up to 85% compared to classic sprinkler systems. Before EconAqua, it was only possible to achieve this with high pressure fine spray extinguishing systems that usually operate at pressures between 100 and 140 bar. EconAqua achieves fire control with operating pressures of less than 16 bar. The EconAqua system is similar in function and structure to a conventional sprinkler system making it simple to understand. In addition, as the design and installation is similar to a conventional sprinkler system the customer will benefit from all the skills and experience of the licensed installer. The excellent performance of EconAqua has been proven in numerous full-scale fire and extinguishing tests under realistic conditions and confirmed by VdS Schadenverhütung GmbH (Approval No. S 4060013). The VdS approval was issued after the system successfully passed all full-scale fire tests, individual testing of system components as well as a detailed review of the product manual. EconAqua systems are suitable for protecting the following risk classifications: LH (Light Hazard) OH1 (Ordinary Hazard Group 1) (which do not involve risks to production) OH2 (Ordinary Hazard Group 2) (only multi-storey car parks / underground garages) 1.2 Areas of application The EconAqua system is a sprinkler system that uses water efficiently, reducing the need to store large quantities of water for fire protection. It also cuts water consumption during system testing and under fire conditions allowing it to be used. It is therefore used where limited water is available, either through lack of available supply or where the customer is concerned about the environmental impact of water usage. The system is also beneficial for areas where the user is concerned about any potential water damage in sensitive or high-value areas. 1
Typical examples of application: Official and government buildings Archives, document and storage rooms (floor space of up to 50 m², partitioned off in F30/T30 quality) Railway stations (without sales areas) Banks Reading rooms in libraries Office and administration buildings EDP rooms < 50 m² (e.g. server rooms, without tape storage) Hotels and restaurants Churches Hospitals, retirement homes and other care facilities Parking garages / underground parking Schools, universities and other educational establishments Penal institutions Hostels, apartment houses Double floors and false ceilings 1.3 EconAqua vs high-pressure water mist systems EconAqua is so far the only water mist extinguishing system approved by VdS which achieves a comparable efficiency to high-pressure water extinguishing systems but by using less expensive low-pressure technology. EconAqua heads have significantly larger outlet orifices - which reduces risk of clogging of pipes or nozzles. Costs are significantly lower as a result of less expensive low-pressure components. Electrical pumps require significantly less power, which in turn reduces connection and running costs. Can be constructed with galvanised pipes, stainless steel pipes, plastic pipes or with pipes installed in concrete, if they are VdS-approved for specific application case. The cost-intensive use of stainless steel pipes, often required with high-pressure systems, is not required for EconAqua systems. Systems are multi-flexible as regards system design. They can be connected to classic extinguishing systems, operating water networks and to drinking water supply systems. In addition, it is possible to connect with classic hydrant systems within a water supply system, since both are operated at similar pressure. In areas that may be affected by frost, EconAqua systems can be designed like a classic dry sprinkler system. 2
2. Case study 2.1 Summary An EconAqua water mist sprinkler system combines: a) price advantages of a classic sprinkler system with b) efficiency of a high pressure system 2.2 Benefits Key benefits an EconAqua system: a) Protection of life, material assets and environment b) Complies with legal requirements (Building regulations) c) Discounted fire insurance d) Efficient alternative to: conventional sprinkler systems high-pressure water mist systems 2.3 Fine spray technology The system uses fine spray technology: Conventional sprinkler system Water mist system Droplet size: > 1 mm Droplet size: << 1 mm Surface area 1 litre water: ~ 3 m² Surface area 1 litre water: ~ 60 m² 2.3.1 Technology A low pressure extinguishing system, which has a low extinguishing water consumption made possible by means of innovative head design: a) Operating pressure: max. 16 bar b) Average droplet diameter: ~ 250 μm c) Density of water application: 1.9 mm/min 3
2.3.2 High efficiency by cooling and smothering effect a) Small droplets vaporise faster absorbing heat and replacing oxygen b) Lager number of small droplets offer a greater surface of water absorbing more heat and improving cooling compared to large droplets of the same volume c) Small drops can be drawn into the fire by air currents feeding the fire, attacking the fire at source 2.4 Components Diagram illustrating typical system components 2.5 Advantages over conventional sprinkler systems: Reduction of required extinguishing water up to 85% resulting in: a) Minimisation of damage caused by extinguishing water b) Less space required for a smaller water supply c) Lower power consumption as smaller flow rate pumps necessary e.g. ~ 11 to 30 kw (instead of ~ 22 to 55 kw) d) Smaller connection to water supply sufficient e.g. ~ DN 50 instead of ~ DN100 e) Less space required for pipe routes in premises as pipe diameters typically 20-40mm instead of 32-65mm f) Cost-saving due to smaller components required and less space required for components 4
2.5.1 Less space required for water supply A: Standard sprinkler pump room B: EconAqua pump room, reduced capacity storage tank: Space-saving ~ 60% C: EconAqua pump room, direct connection to towns mains: Space-saving ~ 80 % Example 1: New office building Savings of space and on-site costs of pump room: a) Construction costs per 1,500 m² b) EconAqua pump room (B), space saving: 15 m² c) On-site cost saving: 22,500-30,000 Example 2: New office building with basement garage a) 20 floors above ground b) 2 basement garage floors c) Construction costs per 1,300 m² d) EconAqua pump room (B), space saving: 200 m² e) Cost saving: 260,000 2.6 Advantages over high-pressure water mist systems: 2.6.1 Improved reliability Reliability is improved for following reasons: a) Comparable effectiveness to a high-pressure water mist system b) Direct connection to drinking water supply c) Special filters or additional treatment of water not required 5
d) Very low risk of clogging due to impurities 2.6.2 Cost advantage Costs are reduced in following areas: a) Potential for direct connection to town s main b) Fire service connection permissible c) Lower sales price and maintenance expenses d) Uses cheaper low pressure components e) Stainless steel components not required f) No special water quality necessary g) System does not need to be continuous checked for clogging h) Can be used as dry system in multi-storey car parks pipework heating not required 2.7 Comparisons Comparison table of benefits Conventional sprinkler system EconAqua High pressure water mist Application of extinguishing water - + ++ Safety against clogging ++ + 0 Required space for piping - + ++ Required space for pump room - + + Sales price extinguishing system ++ + -- Maintenance expenses + + -- Total cost of ownership + ++ - Key: ++ very beneficial, + beneficial, 0 neutral, - adverse, -- very adverse Table comparing cost and effectiveness C A = Conventional sprinkler system Costs B = EconAqua A B C = High pressure water mist Efficiency (application of extinguishing water) 6