First responseWater mist puts out fires at low pressure

Published 23 August 2011

A new water mist system allows for fires to be extinguished from a distance of eight meters; the system’s special nozzles generate a fine mist of tiny water droplets; the water and the propellant nitrogen are non-hazardous, environmentally friendly, and leave no residues

Misting system proves effective // Source: allproducts.com

With a new water mist system, fires can be extinguished even from a distance of eight meters. Siemens says that its Sinorix H2O Jet is meant for industrial environments, including turbines, painting lines, or production equipment.

Special nozzles generate a fine mist of tiny water droplets. The water and the propellant nitrogen are non-hazardous, environmentally friendly, and leave no residues. The company notes that Sinorix H2O Jet won the Innovation Award in the Fire Fighting category at the Expoprotection trade fair in Paris.

The prerequisites for a fire are oxygen, heat, and fuel. If just one of these factors is eliminated, the fire goes out. Depending on the application, automated fire suppression systems use a variety of agents: water, gases, or a combination of gas and water. Water cools down the flammable material and environment and thereby prevents the fire from spreading rapidly.

Water mist systems have several advantages over sprinklers and foam or gaseous fire-extinguishing systems: The water damage that sprinklers cause to expensive furnishings or equipment is avoided, and no salt residues or surfactants from foam extinguishing agents are left behind.

In the past, however, the water mist has been generated by means of high pressure, which makes the installation relatively expensive. This is why, the company says, it has developed a 2-phase technology that uses low pressure.

Sinorix H2O Jet uses a mixture of water and nitrogen to generate a maximum cooling effect — at a pressure of less than sixteen bar with water droplets of 150 to 200 micrometers in diameter. The smaller the water droplet size, the larger the surface area for heat absorption and for smothering a fire. In fact, the company says that when planning a Sinorix H2O Jet system, the Siemens engineers calculate the ideal droplet size for the property or equipment to be protected. The system works with two different types of nozzles:

One is for protection of the objects. It is a patented nozzle that operates according to the Laval principle and can be used to target and extinguish from a distance of up to eight meters. The other nozzle protects objects as well as their surroundings and controls the fire.