Disinfection and Sanitisation: What is the difference?

Cleaning, sanitising, disinfecting, sterilising - What is the difference?

In the Australian/New Zealand/Papua regions, there is often confusion between these terms and at times they are even used interchangeably. Common questions that are asked:

  • Is disinfecting the same as sanitising?
  • Do I need to disinfect or just clean?
  • Do I need to sanitise or disinfect?
  • Is sterilising the same as disinfecting?

There are some fundamental differences in these processes and the products used for each. Whilst this is not intended to be a complete technical guide, here we have tried to give broad overview of the differences.

Cleaning

Cleaning is the removal of any visible particle (dust, food, oil) from surfaces. The process of cleaning usually involves the use of detergent, sometime referred to as soap, diluted with water. Dilutions rates will vary depending on the manufacturers recommendation. A detergent is broadly described as a surfactant designed to suspend oily and greasy particles in water, helping to remove them more easily from the surface to be cleaned. The cleaning process does not necessarily kill germs and bacteria however it will typically remove these pathogenic substances. Cleaning lowers the number of germs and bacteria on a surface and therefore lowers the risk of germs multiplying and viruses or bacteria being spread. Cleaning Is a very important first step to effectively disinfection and sterilising, as cleaning removes any dirt and soil from a surface which could reduce a disinfectants ability to kill germs, viruses and bacteria.

Sanitising

The process of sanitising is a step up from cleaning, however generally denotes a lower level of hygiene than disinfecting. Sanitising does not necessarily clean surfaces or remove staining and dirt. Sanitising is done with the use of a range of chemical, many of which are similar to those use in disinfectants. Sanitising chemicals may be used at a higher dilution rate than a disinfectant. Sanitising will typically aim to reduce the numbers of bacteria to a safe level, compared with disinfection which would aim to kill all bacteria on a surface. Sanitising will remove up to 99.99% of bacteria in less than 30 seconds, which will decrease the risk of infection. Some sanitisers are designed to be “no-rinse” which makes them effective for use in food preparation areas as the last step in a cleaning/sanitisation process for food prep surfaces. Another common application is sanitising children’s toys. It cannot be overstated that in order to have an effective sanitising process, it is very important that the surface has been cleaned first to remove any soiling.

Disinfection

Unlike cleaning, disinfection aims to kill all germs on surfaces with the use of a range of chemicals. Common products used in the formulation of disinfectants include Alcohols, Aldehydes, Ammonia, Chlorhexidine, Chlorine. Whether or not the disinfectant does in fact kill all the viruses on the surface will depend on a range of factors, including;

  • Disinfectant shelf life and quality
  • The suitability of the disinfectant for the application
  • The dilution rate used
  • The dwell time on the surface

Like sanitising, disinfection does not normally clean surfaces or remove staining and dirt. Therefore it is again important that a thorough cleaning process has been completed first in order to achieve optimal disinfection. Disinfection regimes are best performed regularly on areas touched frequently. Examples of this could include lightswitches, door handles, door push plates, keyboards and telephones, access keypads and screens, remote controls, countertops, tapware and sanitaryware touchpoints and more.

Sterilisation

Sterilisation is typically used only in hospital and high grade medical or scientific environments. The sterilisation process is a level up from disinfection, as it destroys all microorganisms on the surface of an article or in a fluid preventing any disease transmission arising from the use of that item. Sterilisation is achieved by a variety of means including heat, high pressure, chemicals, irradiation, and filtration. Due to the higher process costs, sterilisation is not normally used in the commercial cleaning and maintenance field of operations.