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The Importance of Material Understanding in the Decontamination Process

Thu, 14/01/2021

In our ongoing series of articles around the topic of sterilisation processes, and considerations that include protocols, the design of an implement that requires decontamination and sterilisation and other factors to consider, we now move on to a more in-depth look at material design.

Typically, the materials used to manufacture a medical device or implement will be metallic, non-metallic or a combination of these.

Metallic instruments will have properties including high thermal conductivity, and conversely non-metallic implements will have low thermal conductivity, which impacts on the decontamination process in the following way.

Materials with low thermal conductivity experience a greater temperature variance than those with high conductivity, which means that these implements require a different protocol for sterilisation.

The moisture content of a material will also have a bearing on the decontamination process, affecting the heat transfer into the implement and therefore the range of tolerance it needs to bear in order to be properly decontaminated. This factor should be taken into account when categorising the implement in terms of its performance, during which the material should be tested at its most challenging state.

Added to this, materials with high thermal conductivity and equal heat capacity will initially generate more moisture, and also absorb and release heat more effectively, again factors that need to be taken into account when creating protocols and testing decontamination processes.

In terms of the sterile barrier system, it’s essential to know and understand the steam penetration resistance caused by the barrier system, and what materials make up the barrier system so that the impact of the extra moisture can be factored into the decontamination process.

When analysing devices for the purposes of grouping them into select categories, the weight of the device is an important factor – whether processed separately or as part of a collection of medical devices grouped into a single sterile barrier system, this information should be made clearly available, as it pertains to:

  • Heat-up time
  • Cooling time
  • Drying time
  • Exposure time in a mixed weight steriliser
  • The stability of the single or compound material involved in implement construction
  • The amount of condensate and its effect on steam penetration

For more information on setting up correct sterilisation and decontamination systems and protocols, or for training, consultancy and other guidance contact the team at AVM Services today on 01223 254499 or

The Importance of Material Understanding in the Decontamination Process