Pressure Fog®

High Pressure Atomization without an Air Compressor

Pressure Fog® is Armstrong’s most efficient high pressure atomizing humidification solution. Pressure Fog efficiently produces a rich fog to raise relative humidity without the need of an air compressor, keeping energy costs low and environments cool. Pressure Fog is a humidifying system that is ideal for applications that require high water volume with minimum energy use.

Energy efficient, low maintenance, reliable, precisely controlled, and clean. Armstrong believes these five industry needs are priority for humidification systems. Since 1938, Armstrong has been a leading supplier of humidification solutions for corporate environments, museums, hospitals, universities, semiconductor manufacturing, and electronics manufacturing. Customers’ needs are constantly changing and while many of the humidification products are successful in providing desirable indoor air quality, Armstrong is committed to developing and engineering new technology to best suit our customers’ demands.


  • Large capacity range: 250 (113), 500 (227), 1000 (454), 1500 (680), 2000 (907), and 3000 (1361) lbs/hr (kg/hr).
  • Power voltage supply: 240, 380, 480, or 600 VAC, all 3-phase, and 4-wire ground.
  • Unit has a human-machine interface, houses plunger pump and motor and contains the electrical cabinet.
  • Auto or Manual Mode Option
  • All wetted parts are stainless steel and plastic
  • Welded dispersion manifold with threaded nozzles with an output of 7-16 lbs/hr (3.2-7.3 kg/hr)
  • Silent operation
  • Droplet separator to trap water droplets that have not evaporated (used in AHU/Duct application)
  • Odor control
  • Dust compression
  • Direct Area Discharge (DAD)

Low Maintenance, Energy Efficient Evaporative Cooling

Pressure Fog® compliments the Armstrong humidification family by offering a low maintenance, energy efficient solution for evaporative cooling that uses an ultra-clean source of deionized or reverse osmosis water to ensure no blockage of the nozzle orifices, no dust from fog evaporation, and to promote better hygiene. And because of an all stainless steel construction that prevents corrosion or buildup of deposits, Pressure Fog® commits to long-lasting service life. 

Compared to other humidification methods like hydro-pneumatic fogging systems and electric steam humidifiers, Pressure Fog® is the most efficient solution in its appropriate operational environment.

How Pressure Fog® Works

Pressure Fog® boosts demineralized water to 1,000-1,200psi (68.9- 82.7 Bar) using a plunger pump, which transmits the pressurized water to atomizing nozzles. The nozzles then nebulize the water into an array of super fine particles, down to 10 microns in diameter. These minutely sized particles create a fog that allows for quick evaporation and cooling by absorbing heat from the surrounding ambient air.

This adiabatic process of evaporative cooling decreases the temperature of the air being humidified; it follows a line of constant wet-bulb temperature on the psychrometric chart.