How Cold Plasma Removes Smells and Germs

decomposing unpleasant odor in changing room and toilet smells
WOOFAA adopted plasma tech in its algal appliance for public toilets
Lightning generates mighty plasma clean air in large scale

Plasmas are conductive assemblies of charged and neutral particles. Plasmas carry electrical currents and generate magnetic fields. Much like sunlight or lightning does in the atmosphere, cold plasma tube produces natural streams of positive and negative oxygen ions.

The negative ions contain an extra electron while the positive ions are missing an electron resulting in an unstable condition. In an effort to restabilize, these bipolar ions seek out atoms and molecules in the air to trade electrons with, effectively neutralizing particulate matter, bacteria and virus cells, odorous gases and aerosols, and VOCs.

How the Ions Work the Smells and Germs:

  1. Airborne particles are charged by the ions causing them to cluster and be caught in filters.
  2. As they divide to reproduce, bacteria and virus cells bond with oxygen ions and are destroyed.
  3. Odorous gases and aerosols oxidize on contact with oxygen ions and are neutralized.
  4. Oxygen ions cause a chemical reaction with VOCs breaking down their molecular structure.
Plasma Pathogen Removal Rate

Influenza A Reduction

Test Conducted by: Plasma Air, Inc, USA


The 0.2 m3 acrylic test chamber was put into biological safety cabinet. The D5 device and fan were then placed in the test chamber. The virus suspensions were sprayed into the chamber using a compressor-type nebulizer NE-C16 (OMRON) into the test chamber for 5 minutes at an air flow ratio of approximately 0.2 mL/min.

Summary of Results

The device reduced 86.6% of Influenza A virus after one hour.

Plasma Ion Counts Chart

What Are Oxygen Ions?

Ions are molecules or atoms that contain an electrical charge and exist in nature in various sizes. Small ions only last between 30 and 300 seconds before losing their charge, but are extremely active.

Small ion densities range from 900 to 1,100 negative ions and 1,000 to 1,200 positive ions per cubic centimeter (ions/cm3) in pristine natural environments. At sea level ion density is typically around 500 negative and 600 positive ions/cm3. In cities and inside buildings ion levels drop by 80% to 95% and can be barely detectable in small spaces.

As ion density decreases, so does the air quality. By increasing the quantity of both positively and negatively charged small oxygen ions, air quality is improved. This is the basis of plasma ionization technology.

How Cold Plasma Removes Smells and Germs

Plasma Tube Sizing

Single tube commercial quality unit is used in our Wet AOB to remove toilet smells and any unpleasant odor. The number of units and the size of the ionization tubes are actually dependent on the airflow in the system and the severity of the pollution problem.

Video in below shows how fast a plasma tube works out to decompose high level VOC concentration… in seconds as a matter of factly.


WOOFAA integrates Internet-of-Things (IoT) & Indoor-Air-Quality (IAQ) systems for smarter automation features, and thus giving you healthier breathing air and wellness at lower energy cost.

Standalone Air Quality Monitors


Standalone Air Quality Monitors

Wireless Air Quality Monitor Networks


Wireless Air Quality Monitor Networks. Starting one-monitor-one-dashboard, scalable to multiple monitors across floors and even buildings.

Wireless Air Quality Monitor and Controller Networks


Wireless Air Quality Monitor and Controller Networks

Algal Oxygen Bar: Innovative GreenTech and PropTech on IAQ


Algal Oxygen Bar: Innovative GreenTech and PropTech on IAQ

Contact Us

WOOFAA, Sound of Clean Air


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