High-Pressure Water Mist for Firefighting

Facts and Capabilities
The volume of finely atomized water dispersed in close proximity to the flame creates a high quantity of water vapor, which displaces the surrounding air and thus its oxygen, choking the flame.
The transition from the liquid to the gaseous state absorbs a high amount of energy. The enormous increase in surface area created by the atomization of the water exploits the enthalpy of vaporization to its maximum.
In addition, the high-pressure water mist will also suppress smoke gases that are highly toxic to humans and animals. Another effect of the water mist – otherwise only achieved by powder-based systems – is the blockage of heat radiation, which is a significant factor in the propagation of fires.
Fire before it has been extinguished with water mist Fire after it has been extinguished with water mist

High-Pressure Water Mist for Firefighting

How High-Pressure Water Mist Works
Fire test with a power of 11 megawatts: A pre-heated transformer after more than two minutes of pre-burn time
Fire extinction within 30 seconds using less than 129 liters of water

Callies High-Pressure Water-Mist Systems

All the benefits of different fire-extinguishing methods packed into one!

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  • no danger to life and limb
  • low-cost fire-extinguishing agent
  • no advance warning time
  • no detection technology
  • no staff briefing
  • cooling effect
  • local fire extinction at the fire scene
High-Pressure Water Mist
  • smoke gas sluice-out
  • containment of heat radiation
  • low storage costs for extinguishing agent
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Gaseous Fire-Suppression
  • no shading
  • total flooding
  • low consequential damage
  • quick resumption of business, less downtime
  • no contamination from fire water
  • stifling effect
Energy requirement for phase transition from liquid to gaseous
The phase transition during the evaporation process absorbs a tremendous amount of energy, which is withdrawn from the fire. Thanks to their large reaction surface and the gaseous dispensation of the aerosol, HPWM systems have an ideal evaporation ratio in the extinguishing medium.
Little Water – Little Damage
The low quantity of water that a high-pressure water-mist fire-extinguishing system requires – compared to traditional sprinkler systems – not only reduces the amount of water that has to be stored but also the damage in case of activation. For this reason, downtimes in the affected areas will be significantly shorter, thus reducing the overall damage.
High pressure water mist nozzle

HPWM Nozzle Technology

From Water to Mist
Pipes and Nozzles
The piping system consists of a main pipe centrally located in a frost-free environment. Depending on the case at hand, one or more pipes lead to each of the designated fire sections. In each section, the front end of each supply pipe is fitted with a shut-off valve with remote indication. The piping system consists of stainless steel. The main pipe is joined with high-quality press fittings, the distributor pipes and the pipes connecting to the nozzle are joined with cutting rings.

The water consumption per nozzle varies between 2.8 and 25 liters (0.74 and 6.6 gallons) per minute, depending on the characteristics of the room. This means a significant reduction of water consumption, compared to a traditional sprinkler (80–250 liters = 21–66 gallons per minute) and also permits smaller pipe diameters. The main pipe usually has a diameter of only 33 or 42 mm, and pipes leading to the nozzles have diameters of 10 or 12 mm, allowing extremely simple installation.

Nozzle heads may be supplied with either open (deluge) nozzles for “dry piping” systems or closed nozzles with “melting fuses” or “glass bulbs” for “wet piping” systems.
Dry Piping Systems
Open-nozzle systems consist of a nozzle head with micro-nozzles or of separate micro-nozzles mounted directly on the supply pipe. With an open nozzle, the water will be atomized as soon as the high-pressure pump is activated either manually or by sensors signaling a fire.
Wet Piping Systems
Closed-nozzle systems also consist of nozzle heads equipped with micro-nozzles, but they are secured with glass or plastic bulbs that will melt as soon as the temperature exceeds a certain threshold – starting at 56 °C (133 °F), various options are available – and thus release the water. Each nozzle is equipped with a filter to prevent clogging. Each nozzle head is available in polished chrome-plated brass or polished stainless steel, the latter for use in an aggressive environment. For design or architectural purposes, nozzles may also be supplied in various colors on request. The water consumption will be determined individually in each case, based on the existing fire load, and it can be adjusted to the actual requirements anytime by exchanging the micro-nozzles in the nozzle head.
To activate the system, a trigger system for the high-pressure pump is required. The system may be activated either by a signal from a pressure controller (drop in pressure triggers nozzle, closed system) or from a fire detector or fire alarm system. In addition, the system may be activated manually. These versions may be fed by automated as well as semi-stationary Callies vehicle systems.


High-pressure water-mist systems have a name, and that name is Callies.
The development of our high-pressure water-mist systems, which are designed for fire prevention and protection, has been guided by our many years of experience and knowledge gained in active service. For this reason, our focus was initially on the development of mobile high-pressure systems, which are now employed by fire services around the world and have proven their efficiency.
Planning, Construction, and Maintenance
With our pioneering work in this area, we have acquired an extraordinary wealth of experience in the development, design, and construction of water-hydraulic systems over many years.

Our priority lies in securing economic assets to the fullest satisfaction of or clients and customers. In our view, the only way to achieve this is through top-quality systems engineering, a goal we strive to achieve without any compromise. For this reason, when we manufacture our products, we only use pumps, valves, and stainless-steel materials destined for a long lifetime.
Customer-Oriented System Solutions
Our fire-extinguishing systems, which are customized according to the specifications of each of our customers, are designed by a team of experienced experts focusing on your specific needs. These systems may be adapted to general circulation areas as well as the protection of key industrial and manufacturing sites and facilities.

Callies GmbH thus offers an extraordinary range of high quality fire-safety equipment for all walks of life.
Employee is planning a concept for a fire-extinguishing system with modern computer software

Conceptual Design

From Planning to Execution
With Callies, your project is in good hands!
From the earliest planning stages on, we will support you with our comprehensive expertise in finding the perfect concept. You will benefit from the diverse education and training our engineers and technicians have received. In addition, all of them hold leading positions in the volunteer fire department. Whether it’s a mobile, a semi-stationary, or a stationary system in a building complex that you are looking for: our multi-talented team covers every field, from expertise in electrical engineering to the technical planning of fire safety in buildings. We will gladly furnish you with a cost estimate, based on construction and facility plans, and advise you on site. If you wish, we will contact a certified inspector of your choice at an early stage to ensure that the plans comply with all pertinent regulations.
We are extremely meticulous when it comes to detailed design, which is either performed separately in a CAD system or, at the customer’s request, integrated into existing building plans. In addition, you will receive a piping and instrumentation diagram (P&ID), pressure-loss calculations, detailed technical documentation (such as data sheets, wiring diagrams), and a system owner manual for each system we supply. Coordination with fire-detection devices will also be handled by Callies. The setup of detector groups and the dispatch of fire-extinction commands under predefined conditions as well as the integration into fire-department guiding and orientation diagrams are also part of our planning.
Consultation, Assembly, and Construction Management
The assembly and installation of our systems is executed by a dedicated assembly team in close contact with our specialized construction management, which also visits the construction sites regularly and attends meetings, in order to give advice on complex issues wherever it is required. You may also entrust us with coordination with other crafts, such as electricians, fire-alarm technicians, or utility engineers.
Testing, Approval, and Documentation
Callies will, of course, accompany the official inspector certifying the system. Experience has shown that in many cases, certain sections of the firefighting system are already put into service while construction is still ongoing. Proper documentation, briefing, and handover are of paramount importance. We vouch with our name for quality “without ifs and buts.”

Comprehensive Solution

  • Dry-Pipe Systems

  • Wet-Pipe Systems

  • Mobile Systems

  • Control Technology

  • High-Pressure Water Mist

  • Planning

  • Maintenance

  • Components

One-Stop Shopping

Individual and personal
“Quality is when the customer returns, not the product.”
Project Survey
In order to provide you with the best possible advice, it is imperative that we have a complete and comprehensive overview over your vehicle-based and stationary system projects. In the case of a vehicle installation, we cooperate closely with our customer and the vehicle manufacturer. For projects involving the installation of stationary extinguishing systems, we will always seek an on-site survey with our customer-to-be, in order to obtain an overall impression of the surrounding conditions as well. Only this way will we be able to offer you solutions that perfectly meet your goals and needs. So we take the time to listen to you and thus build a solid foundation for a successful long-term partnership.
Solution Proposal
The plans and data gathered and the common targets defined at the initial project survey will then be evaluated and summarized into a coherent concept. You will benefit from our specialists, our wide range of products and services, and our in-depth knowledge of the industry.
Decision and Execution
With the proposal we make and the technical solutions we suggest – based on our profound expertise –, we will provide you with a dependable plan that suits your needs. In all this, transparency is of utmost importance to us.

If you accept the technical solution we propose, we guarantee the competent and professional installation of the system plus our qualified and experienced pipe specialist’s excellent workmanship.
We will stay closely in touch with our customers after the project has been completed. This allows us to respond quickly and flexibly to changing conditions, e.g. in production or storage, and to implement necessary adjustments with our well-assorted product portfolio on very short notice. If need be, we will work out a new protection goal, based on the existing pump system, with necessary alterations in pipe runs and/or nozzle arrangement. A personal consultation that focuses on the issues at hand will always be our priority. Anytime.