protect what matters

Sterile Matters have developed a Coronavirus (COVID-19) decontamination strategy, with guidance and training from public health and decontamination professionals, enabling our teams to provide Coronavirus specialised sanitation services. 

Our sanitisation process includes the use of virucide/biocide solutions on all surfaces, focusing on touch points, including appliances, furniture, desks,  doors, floors, kitchens,walls and toilets, etc, depending on your requirements.

With the current outbreak of COVID-19  now affecting Irish businesses, schools and universities, Sterile Matters  has taken special measures to help address the potential epidemic and reduce its impact . With expertise in fogging  and specially trained staff, we are able to offer specialised   decontamination services to disinfect  sites. Our highly trained teams, using specialised equipment, can quickly and professionally decontaminate most sites, including offices, schools, universities, clinics, care homes, cinemas and shops.

What Are Cold Foggers

A cold fogger is a device we use to fight a virus both indoors and outdoors. We can also use them to get rid of moulds and unpleasant odours.

A cold fogger is “cold” because it’s the opposite of a thermal fogger. Cold foggers don’t use heat to vaporize the fogging liquid and turn it into a fog. Instead, they use cold spraying methods, which, in most cases, use high amounts of air pressure to spray the fogging liquid out in tiny particles.

The most popular type of cold fogger is the ultra-low volume (ULV) fogger. Most of the time, ULV foggers are considered the same as cold foggers.

How Do They Work?

Inside the casing of a cold fogger is an electric motor. This is the main part of a ULV fogger since it sprays the fogger liquid out as small particles. The power of the airflow will depend on the power of the motor.

Some cold foggers use oil-based fogging solutions while others use water-based solutions. There are foggers that can be used with both types of solutions. The fogging solution goes in the tank which is either in the body of the fogger or attached to the bottom of the machine. We don’t use oil based products because of fire issues.

When you turn the fogger on, the electric motor will pump the fogging solution out of the tank. It then sprays the liquid out through a special nozzle located on the front of the fogger. This nozzle turns the fogging solution into small particles.

Particle Size

The advantage that ULV foggers have over thermal foggers is that they allow you to control the particle size. On standard ULV foggers, you’ll have the option of setting the particle size from 5–30 microns. You can adjust the droplet size a ULV fogger produces by either turning a flow valve or pushing a button on the fogger, depending on the model you have.

Higher airflow will produce larger particles while lower airflow will produce smaller particles. This is definitely useful if you need to fog in different areas.

You might want to use smaller particles indoors since they stay in the air for longer and can reach smaller gaps and holes in the walls and floor as well as the spaces behind furniture and other tight spaces. 

What is Thermal Fogging?

Thermal fogging is the generation of ultra-fine droplets in a range of 1-50 µm using thermopneumatic energy. Liquid substances are vaporised at the end of fogging barrel (resonator) and form ultra-fine aerosols by condensing on contact with cool ambient air, on being ejected, to create dense visible fog-clouds. Pure oil solutions or aqueous liquids with a glycol component are especially suitable for this purpose.

Uses of Thermal Fog.

Thermal fogging is used for any viruses and pest  control task where active substances should be uniformly distributed, even in inaccessible places, without leaving undesirable residues. This fogging method is the solution for treating large areas and spaces with a minimum quantity of problem solving solution, less operational work and with little harm to the environment (less residues,no penetration into the ground).

Functional Principle of a Thermal Fogger

Thermal foggers are equipped with a pulse jet engine, which, while extremely light-weight,

has a substantially higher Output capacity than a conventional fuel engine.

 The pulse jet engine does not have any mechanically moving drive components.

  • It consists of a bottle-shaped combustion chamber similar to a rocket engine which opens into a long exhaust pipe (resonator).
  • An initial mixture of fuel and air is supplied through non-return valves into a combustion chamber, and is ignited by a high-tension spark obtained from a battery powered electronic ignition device connected to the plug for a few seconds.
  • The fuel is regular-grade petrol and about 2 l/h is used on the smaller machines.
  • Once the machine has started, the high-tension spark is no longer required and is automatically stopped.
  • The exhaust gases from the combustion chamber escape as a pressure wave at high velocity through a long pipe of smaller diameter than the combustion chamber, and draw in a fresh change of fuel and air from the carburettor (s. figure 3).
  • If operating with the correct mixture, there are about 80 – 100 pulsations per second, slightly irregular with maximum noise similar to a chain-saw.
  • By means of a non-return valve the pesticide tank is also pressurised (with 0,2 – 0,4 bar),and when the machine has warmed up, after about 2 min. running, a valve tap is opened to permit the controlled and regulated flow of solution through interchangeable dosage nozzles, fitted into the end of the resonator.
  • Near the outlet of the resonator, the chemical to be atomised is injected into the hot exhaust gas stream. A part of it gassings, and it condenses to form billions of ultra-fine fog droplets.