clean room foggers, DI water fogger used in smoke studies to visualize airflow and turbulence, and used in airflow recovery

Applied Physics, Inc.

Clean Room Fogger, CRF4

Ultrapure Nitrogen Fogger, AP35


Calibration Wafer Standards

PSL Wafer Standard

Contamination Wafer Standards

Particle Wafer Standards

Cleanroom Fogger, CRF2

LN2 Nitrogen Fogger

PSL Spheres, Polystyrene Latex Beads

Silica Nanoparticles in DIH2O, 15ml or 100ml volume

Smoke Studies to Visualize Airflow and Turbulence

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1-720-635-3931 or 303-999-6837

Clean Room Fogger, DI Water Fogger and Portable Fogger

The Clean Room Fogger is used in smoke studies with DI Water or WFI water to generate about 9 cfm of pure fog for about 50 minutes with on demand fog control. No contamination of any kind is created and no clean up is required. Clean room airflow, turbulence, patterns and balance of airflow are visualized in smoke studies of pharmaceutical ISO suites, sterile rooms, bio safety cabinets and barrier isolators. The CRF2 Clean Room Fogger supports airflow visualization guided by ISO 14644-3, Annex B.7 Airflow Direction Test and Visualization; USP 797 Insitu Airflow Analysis (and future USP 800 for Hazardous Drug Compounding in clean rooms); NSF 49 National Safety Foundation and Semi-Standards Clean Room guidelines for airflow visualization and analysis. It also supports airflow recovery guided by ISO 14644-3, Annex B12 Airflow Recovery Test using 0.5 micron to 2.0 micron PSL, polystyrene latex spheres.

CRF-2, Clean Room Fogger: 9cfm fog / minute for 50 minutes operation, 57 ml Fog Density/Minute - Request a Quote

The CRF-2 will satisfy many airflow visualization in pharmaceutical ISO suites and semiconductor clean rooms. This small, easy to use tool will introduce you to the benefits of using a DI Water fog for visualizing airflow and turbulence in controlled contamination areas.

Ultrasonic foggers can be easily compared in fog performance per dollar cost by calculating the actual Fog Density output over time!

Fog volume and Fog density are the two needs when buying a fogger. Fog density is usually unknown and not understood, but is the second most important reason to use a fogger; as density controls the distance the airflow patterns and turbulence will be visible. To calculate fog density, you need the actual fill volume of the fogger and the operating time of the fogger. Ultrasonic foggers use a ultrasonic transducer under water, which then is activated to stimulate fog vapor droplets that are pushed into the airflow to visualize patterns, turbulence and dead spots. Which ultrasonic fogger is the best for the money spent? Most ultrasonic foggers operate with 1 liter to 4 liters of water volume, when filled. Each ultrasonic transducer assembly requires a minimum of 500ml of static water around it before it can turn on; thus foggers with 2 ultrasonic transducer assemblies require 1 liter of static water at the bottom of the fogger before the fogger will turn on. Fogger density is calculated for a 1 Liter Fogger, operating for 60 minutes as follows: (1000ml - 500ml static water) / 60 minutes = 8.3 ml fog density and perhaps 4 feet of lightly visible airflow. A 2.5 Liter, single transducer fogger operating at 90 minutes would calculate fog density at: (2500ml - 500ml static water) / 90 minutes = 22.2 mL fog density per minute, providing about 5 feet of airflow visibility. The CRF2 fogger uses 4 liters and a single high output transducer assembly using 10 piezo sonicators. CRF2 fog density is calculated: (4000ml-500ml static water) / 50 minutes operation = 57 ml fog density. For ultrasonic foggers using a high output transducer assembly, the CRF2 Clean Room Fogger produces the highest fog density of any ultrasonic fogger sold in the semiconductor and pharmaceutical industry today.

Clean Room Fogger, CRF-2 Features - Click here for Clean Room Fogger video

Clean Room Fogger
  • ultrasonic transducers produce 9cfm of fog for 60 minutes
  • Easy Fill Water Port to fill 3.5L of DI Water or WFI Water
  • Water Level Fill Indicator is on left panel
  • Carry Handle provided for operator convenience
  • Polypropylene enclosure offers a clean, lightweight fog operation
  • Transducer life: 5,000 hours
  • Optional Fog Curtain Wand converts fog stream output to a wide fog pattern, plugs into Fog Hose
  • Optional Remote Power Cable/Switch operates fogger inside Barrier Isolator or behind closed walls
  • Optional Rolling Carry and Storage Case
  • 2" Diameter (50.8 mm), white fog hose is included, which telescopes from 28" (71.1 cm) to 82" (208 cm)
  • Power Supply (120VAC or 220VAC) included along with a 5 meter power cable
  • Easy to use with less than 1 minute set up time
  • Constant on operation or instant On/Off operation
  • Paperless operation with Instructions and Applications labeled on right side of enclosure
Clean Room Fogger and fog curtain wand

Pharmaceutical Suites, Semiconductor Clean Rooms

  • Supports Recovery Test evaluation, 100:1 recovery time as defined in ISO 14644-3, Annex B.12
  • Supports airflow visualization tests for ISO 14644-3, ANNEX B.7
  • Supports airflow visualization tests for NSF 49 National Safety Foundation guidelines
  • Supports airflow visualization tests for Pharmaceutical USP 797 Insitu Airflow Analysis
  • Supports airflow visualization tests for SEMI Standards Guidelines
  • Airflow balancing
  • Leak detection in ducts
  • Laminar flow tests
  • Wet bench exhaust optimization
  • Personal safety exhaust verification
  • Chemical process equipment ventilation tests
  • Pressure balancing between rooms and spaces
  • Visualization of airflow patterns and turbulence
clean room fogger
clean room fogger carry case   OPTIONAL Carrying Case
cleanroom fogger, carry case

Specifications, Clean Room Fogger- Request a Quote

Metric CRF2 Cleanroom Fogger CRF4 Cleanroom Fogger
FOG Duration about 50 minutes about 45 minutes
FOG Volume Output 0.25 cubic meters / minute, constant output 1.25 cubic meters per minute, adjustable fog volume and adjustable flow rate
Total FOG Volume about 12.5 cubic meters, pure fog, during 50 minute cycle about 56.25 cubic meters, pure fog, during 45 - 90 minute cycle
Fog Density (ml/minute) supports visible fog distance 57 mL per minute converted to pure fog 170 mL per minute converted to pure fog
Visible Fog Distance 7-8 feet visible airflow distance 10-15 feet visible airflow distance
FOG Type Ultrasonic Fog using DI Water or WFI Water Ultrasonic Fog using DI Water or WFI Water
Class of Clean Room Use Class 1 to 10,000 Class 1 to 10,000
Compatible Guidelines USP 797 Insitu Airflow Analysis, ISO 14644-3 Annex B7, Federal Standards 209E in Semiconductor Cleanrooms USP 797 Insitu Airflow Analysis, ISO 14644-3 Annex B7, Federal Standards 209E in Semiconductor Cleanrooms
Type of Room Clean Rooms, Sterile Rooms, ISO Suites, Medical Rooms Clean Rooms, Sterile Rooms, ISO Suites, Medical Rooms
Water volume 3.77 liters 10 liters
Useable Water Volume 3.25 Liters
7.650 Liters
Method of Operation Direct Switch Control, Cable Remote Control
Touchpad Control or Wireless Remote Control
Method of Movement Hand Carry Enclosure
Hand Carry Enclosure
Liquid Weight 3.75 Kg Water 10 Kg Water
Standard Power Requirements 110 VAC, 50/60 Hz, 10A 110VAC, 50/60 Hz, 10A
Optional Power 220VAC, 50/60 Hz, 15A; 100VAC 50HZ, 15A 220 VAC, 50/60 Hz, 10A; 100VAC 50HZ, 10A
Dimensions, Inches 10" H x 9" W x 11" D 12" H x 13" W x 22.5" D
Dimensions, Metric 254 mm H x 227 mm W x 280 mm D 305 mm H x 330 mm W x 572 mm D
Full Weight 12.5 lb. 44 lbs


The Clean Room Fogger is used in smoke studies and often called a smoke generator. Although often referred to as a smoke generator, the output is a pure fog and does not require any cleanup after use. Operating instructions are noted on the right panel of enclosure.

Theory of Operation: Ultrasonic cavitation using DI water or Pharmaceutical WFI Water. Use of any other liquids or chemicals will void the warranty.

The transducer life is ~5000 hours, which is protected from electrical damage when water level is too low. The water level sensor will interrupt the input voltage to the transducer module, should the water level drop to a low level to . This ensures long life and reliability.


  1. The clean room fog generated by this device contains microscopic droplets of DI water. AVOID USING IN IMMEDIATE VICINITY OF ELECTRICAL APPLIANCES, WATER SENSITIVE PRODUCTS AND EQUIPMENT.
  2. The fan will operate with no water in the reservoir with the power switch in the ON position. This will aid in drying when the chamber is drained.
  3. To increase drain plug tension, remove the plug, rotate clockwise (CW) the front latch while holding the rear metal disk.
  4. The clean room fogger is intended to be used on a flat surface, on its feet. Tipping the fogger with water in the reservoir will damage the fogger. DO NOT OVERFILL OR TIP THE FOGGER.

Portable Fogger, CRF2 Cleanroom Fogger - Request a Quote

The CRF-2 provides portability using the carry handle on top of the fogger. While carrying the fogger in this manner, it is important not to slosh the water around inside the water chamber. Should you need to move the fogger while water is inside the water container, mover the fogger with slow movements, so that water does not splash inside the fogger.

Which Clean Room Fogger or Smoke Generator Is Best For My Applications?

Cleanroom UltraPure Fogger, AP35 Fogger, 5.0 cubic meters fog/minute at 533ml fog density with 20-30 feet visible fog, LN2 + DiH2O or WFI Water, 75 minutes operation, adjustable fog volume and adjustable airflow with touch pad control and wireless remote control.
  • When high fog purity, high fog volume and long visible airflow is needed
  • To visualizing airflow in large clean rooms, ceiling to floor
  • To fog exit velocity must not create turbulence
  • To needing to do 3D airflow modeling of airflow
  • When needing to do visualize airflow in larger cleanrooms
  • When 90 minutes of high purity fog duration is needed
  • When fog visibility of 20-30 feet distance is required
  • To fog Class 1 to Class 10,000 semiconductor, medical, pharmaceutical clean rooms

* Use Hand Gloves and Face Shield when filling LN2
Use 16M ohm DI water or WFI Pharmaceutical Water
Clean Room Fogger, CRF2, 0.26 cubic meters fog/minute at 57ml fog density with 7-8 feet visible fog, Di Water or WFI Water, 50 minutes operation, refill and restart.
  • When budget is lower, basic Fogger OK, minimal output turbulence
  • When 50 minutes of fog duration is useful with quick turnaround by refilling and restarting
  • When fog visibility for 7-8 feet distance is acceptable
  • When fogging fume hoods, glove boxes, small areas
  • When fogging Class 10 or above in semiconductor or pharmaceutical areass

CRF4 Fogger, 1.25 cubic meters fog/minute at 170ml fog density with 10-15 feet visible fog, Di Water or WFI Water, 45 minutes operation, refill and restart, adjustable fog volume and adjustable airflow with touch pad control and wireless remote control.
  • When you need more fog than CRF2 with adjustable fog volume, adjustable airflow velocity, combined with wireless remote control
  • When fog visibility for 10-15 feet distance is needed
  • When 45 minutes of fog duration is useful
  • When fogging bio safety cabinets, barrier isolators, small cleanrooms
  • Class 1 or above in semiconductor or pharmaceutical clean rooms
  • Can be operated inside a barrier isolator, inside a bio-safety cabinet or behind a closed room

Fogger Technology

The three types of foggers manufactured for use in the semiconductor and pharmaceutical industry are described below.

Ultrapure LN2 Fogger: This type of smoke generator or clean room fogger provides the highest volume, density and purity of fog. Purity is created by bringing the water to a high temperature, creating a vapor, while simultaneously using gravity to remove the residual mass from the vapor. This process removes any bacterial agents and residual particulate matter from the vapor. The pure vapor is then passed over an LN2 bath, which naturally boils at room temperature. The water molecules bond with nitrogen molecules, creating a nominal 3um fog droplet. The volume of water and nitrogen molecules that combine is extremely high in quantity, creating a dense, high volume, ultrapure fog output with exit temperatures of about 78 degrees F with an exit pressure of less than 0.5 lbs, so as not to disturb the surrounding airflow. The fog is ultrapure leaving minimal, if any, trace particles behind. It evaporates to its gaseous hydrogen, oxygen and nitrogen components, which are natural to the Cleanroom environment. The high density of the fog increases the duration and travel distance of the fog. This fogger can be used in a Class 1 - 10,000 cleanroom environments of pharmaceutical and semiconductor facilities; such as sterile rooms, hospital rooms, medical rooms and cleanrooms.

DI Water Fogger: This type of fogger has less fog density (less capability to visualize airflow) than the UltraPure Fogger described above, but more density than the CO2 fogger described below. The DI water fog is generated by atomizing DI water into water droplets, which are nominally 3-10um in size. The water droplets may contain residual particulate matter remaining in the DI water, but this would be very trace amounts. If the facility manager operates a class 10 to Class 10000 Clean room, the use of a DI Water Fogger poses no problem. However, Cleanroom Engineers who manage facilities operating at Class 1 to Class 10 performance may desire to use an ultrapure fogger. Although some DI Water foggers are described as ultrapure, unless the DI water is vaporized to remove bacterial agents and residual particulate matter, the fog is not ultrapure. The 3-5lb output pressure of a DI water fogger also distorts the airflow patterns, thus adding to the turbulence. The temperature output is typically less than the surrounding room temperature, thus a fog generated from the atomized water droplets will sink momentarily in a typical 70 degree room temperature.

CO2 Fogger, CO2 Ice and DI Water: This type of smoke generator, CO2 Fogger, is designed for low volume, non-process critical applications such as bench airflow testing. The fog is created using CO2 ice as the fogging agent, combined with DI Water or WFI water. The fog is generated by evaporating CO2 ice with warm water and is ideal to visualize airflow and turbulence for short periods of time. The fog starts out with a large volume of fog at perhaps 10cfm, but as the CO2 ice evaporates, the fog volume then begins to decrease until no CO2 ice remains. The advantage of a CO2 fogger is the high initial density, making it useful for video applications; and the CO2 fogger is portable as it can be taken into a clean area with no power cords required during the fog process. The output starts at about 9-10cfm and slowly decreases to 0 CFM over a period of 8 - 12 minutes, depending on how much CO2 ice volume is placed in the warm water.

Smoke Sticks and Glycol (glycerine) Foggers

Smoke Sticks are used in some Pharmaceutical Clean Rooms around the world. Below is a discussion on the use of smoke sticks used to visualize airflow and turbulence?

A smoke stick is often used visualize airflow turbulence, but smoke sticks are filled with particulates and chemicals. Smoke is created using chemical reactions; thus the smoke is SPUTTERING (sputter) or popping out of the smoke stick in a non-consistent pattern with velocity, but little volume. It is a particle smoke, compared to a visible, pure water based fog, thus smoke sticks are a contaminating smoke. The smoke stick generates an inconsistent flow or pattern of smoke, but it is low cost, which is why some managers allow use of smoke sticks in their Pharmaceutical clean rooms.

Compare a smoke stick to a Clean Room Fogger or an UltraPure LN2 fogger, both which produce a constant volume of fog with a consistent fog output and pure fog. Di Water foggers produce a consistent flow of visible water vapor, which enters the airflow to visualize the airflow patterns and turbulence, then begins to evaporate, returning back to the hydrogen, oxygen and nitrogen components that we breathe. No particulate contamination, no chemical contamination. Water based foggers produce a constant volume of fog at a constant rate, which provides consistent visualization of airflow patterns and turbulence. The Smoke Stick has to be waved around to see what kind of airflow pattern there is, while a Di Water fogger is simply placed in position and produces a flow of fog that can be directed 360 degrees to easily describe the airflow patterns and turbulence. In addition, tubes are now available to create "fog curtains", or a wall of fog, which smoke sticks can not produce.

How many smoke sticks are used per smoke cycle? How much labor is needed to clean up after smoke stick use. Do you need to Clean all the walls where the smoke stick was used. How did the chemical particulates and particles affect the process area? These are critical questions for a pharmaceutical manager. Did the contaminating particles and chemicals get into the drug process?

How much labor is used to cleanup after smoke stick use and if the cleanup did not get every chemical particle, then some smoke chemical material is added to the Pharma process or trapped in a filter somewhere, until it escapes into the Pharma process. That is a quality control issue for that company using smoke sticks.

The low labor cost of using smoke sticks is the reason facility managers may use smoke sticks, but are the chemical and particulate effects to the pharma process being analyzed? Non-contaminating fog does not emit particulates, requires less labor and does not contribute any unwanted chemicals to the Pharma process. A Di Water Fogger provides these advantages in fog volume, fog consistency and fog purity, which easily outweighs the low cost of smoke sticks, the high cost of labor for cleanup and the detrimental affects to quality control!

Smoke Sticks - quality side of the drug product: The smoke chemicals are not of the same chemistry as the drug product, thus smoke chemicals and particulates could migrate into the drug process. There is no guarantee the cleaning process removed all the unwanted particulates and chemicals, from for example, a glove box or isolation box. The chemicals and particulates eventually migrate to the air filter system, which is not 100% effective. If this is the case, the quality and purity of the drug process is affected. Drug quality is the basis of product credibility, which is a valuable asset in customer relations.

Smoke Sticks - labor side of the drug product: The smoke is generated by a chemical reaction, which causes the smoke to sputter into the environment. The smoke is inconsistent in volume, thus the smoke stick is unpredictable for airflow visualization. The chemicals migrate to equipment and walls, which then must be cleaned, and requires an added labor cost. The use of Smoke sticks generates an inefficient smoke, not a consistent fog.

Glycol Foggers - typically use water combined with glycol liquid, which has a long strand, glycol molecule. This combination produces excellent visible fog; however the long strand glycol molecules degrade HEPA filters by clogging the filtration material, which decreases airflow efficiency. An odor builds up eventually in the filter, when using glycol fog. In most cleanrooms, glycol is considered a particulate contaminate, as it needs to be wiped clean from the clean room. This requires additional labor and manpower. In a pharmaceutical process, how does one clean 100% of the glycol residue from the clean room? How much of the glycol residue enters the pharmaceutical process?

A Di Water Fogger produces a water (H2O) droplet that evaporates back into hydrogen and oxygen, the air we breathe. No clean up is required, at all. No additional time delays and clean up labor is not required. The fog is consistent in volume and constant in output to describe the airflow patterns and turbulence. These are equipment, quality and application concerns to consider when the need for airflow visualization is considered.