... and choosing the right fogger.


Chemical or bio-fogging has long been an effective way of sanitising enclosed spaces, but what was once a highly specialised, expensive cleaning technique reserved for specific industries, like medical, food processing and necessarily sterile environments, is now available to us all. As a society we are all very aware of the risks posed by the winter Norovirus vomiting bug, MRSA infections in hospitals, and more regular and often lethal swine, bird flu and coronavirus pandemics.

Advances in biocidal technology have proven categorically that bio-fogging is both safe and effective. The biocide particles in the mist or fog are so small that they remain suspended in the air long enough to kill airborne viruses and bacteria. The biocide also eliminates pathogens on surfaces, including ceilings and walls as well as furniture and floors whilst leaving enclosed spaces completely safe for human use in just 20 minutes.


When it comes to dry or wet fog produced by our range of machines, the main difference is the droplet size.

Dry fog usually has droplets between 10 to 15 microns in diameter. This is because the droplets are so small that they create a seemingly dry fog.

Fog that has droplets of 20 to 30 microns in diameter is considered wet fog. This fog appears more like a mist than a fog.

All fogs whose droplets are above 30 microns are usually mists or sprays, rather than fogs.

Most cold or ULV foggers can disperse dry and wet fog. Their nozzles allow you to regulate both the spray volume and droplet size within a range of 5 to 50 microns. As long as you keep the droplets small, you’ll get a dry fog.

If you adjust the machine to produce a fog with droplets that are 20 microns or larger, you’ll have a wet fog.

Larger droplets are better for applications such as disinfection, mold control, or targeting specific areas with an insecticide. These larger droplets mean that the fog will lightly wet specific surfaces and coat them thoroughly with the chosen solution.

Wet and dry foggers differ based on the fog they emit.

Most thermal foggers are dry foggers because their mist usually consists of droplets of around 10 microns in diameter. These foggers are perfect when you need to distribute the fog over quite a large area. This is because the smaller particles will be able to diffuse widely and travel quite far thanks to air currents and wind.

The downside to this is that the fog might not thoroughly cover the entire area you wanted to treat. This means that it might be better to fog the area at least twice for more complete coverage.

No matter which kind of foggers you use – dry, wet, cold, or thermal – you should experiment to see which droplet size best suits your needs. This can differ based on:

  • the weather conditions (very windy v less windy)
  • the treatment area (indoors or outdoors),
  • the liquid used (water- or oil-based solutions)

When you consider this, it should be easy to  choose the right fogger.

Still confused? Call us on 0330 133 2532 or submit an enquiry