Holchem Insights: Disinfection Techniques

Blog | 7 August 2017

Here at Holchem we advise our clients on the correct type of disinfection technique to suit their requirements. Here's an insight into the three methods; the application technique depends largely on the type of surface being disinfected.


1. Spray Disinfection

Spraying disinfection is a versatile and economic method that gives good coverage and is the most common method for applying disinfectant to surfaces.

Any pooling of rinse water needs to be removed from surfaces before the disinfectant spray is used; application can be carried out in a variety of methods including:

  • Small trigger sprayers
  • Pump-up sprayers, such as Duraspray
  • Compressed air driven sprayers, such as PD400 or Dema Sprayers
  • Via a high pressure washdown system using a high-pressure injector
  • Via a medium pressure system, either mobile or static.


2. Soak Disinfection

Soak disinfection is highly effective due to the full immersion of items into disinfectant.  This method is mostly confined to small items such as utensils, knives, cutting boards and small machinery parts.


3. Aerial Disinfection (Fogging)

Primarily carried out in high care processing environments particularly cheese manufacture, salad, sandwich, ready meals, cooked meats and dairies.

Certain food processing environments may require fogging to ensure a reduction in airborne microorganisms that could come from sources such as low risk areas, people and aerosols; with sampling identifying where this needs to take place.  Fogging should only be conducted after all cleaning and disinfection of food contact surfaces has taken place, and never as an alternative to surface disinfection. It is typically carried out using a disinfectant solution applied via a fogging unit.

Several types of fogging units are used throughout the food industry: 

  • Trolley Units powered by compressed air are completely portable and hold 25 litres of diluted disinfectant solution.  Output is a constant 0.50 l/min. Particle size is dependent on air pressure and is variable from sub-micron to 100 micron and appropriate for fogging rooms of a volume up to 300m³.
  • Built in systems will typically be used for production areas larger than 300m³.  The disinfectant fog is generated by the system mixing compressed air and diluted disinfectant solution at a number of installed nozzles.