Cambridge University Hospitals - NHS
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Role of AE(D) Staff in driving Steam Quality

Wed, 26/01/2022

One of the most important aspects of maintaining patient and staff safety within hospital environments is preventing infection, with steam quality at the forefront of decontamination and sterilization across multiple areas – most important of which is the reliable and consistent sterilization of reusable medical devices.

The quality of the cleaning, disinfection and sterilization processes is heavily reliant on steam as the most reliable and effective method, with temperature and pressure of steam quality a key factor in achieving acceptable levels of decontamination.

To ensure that the quality of steam produced and used in the decontamination cycle remains at optimal levels, AE(D) staff need to take the lead on driving improvements in steam generation systems.

Factors that must be considered in the steam production and delivery cycle include:

Steam for Safe Sterilization 

One of the major issues faced by hospital staff is the presence of ‘wet packs’, which occurs when wet spots or patches appear on packaging that illustrates that water has been in contact with the device, and drawn into the packaging chamber. A ‘wet’ pack or tray of instruments is usually detected as part of the Sterile Services (SSD) product release protocol. On very limited occasions a slightly damp pack may be give a little extra time to dry sufficiently but generally the pack must not be used for the clinical treatment of patients & be re-worked according to the Department protocol as soon as possible.

Persistent episodes of wet packs warrant further investigation with the expert assistance of both your Authorising Engineer, AE (D) & Authorised Person, AP (D) to eliminate steam based issues & include the use of Steam Quality & Steam Purity Tests. Root causes can include:

  • Poorly draining steam traps between the steriliser and boiler (a sudden demand for steam can draw water out of a full trap)
  • Severe pressure fluctuations in the main steam lines
  • Priming of the boiler leading to carry-over of water in the steam line

Other more obvious causes of wet packs can include:

  • Poor loading of Sterilizers with too many heavy instrumentation sets. Ideally a mixed load should be preferred with heavier trays on the lower shelves, lighter in the middle with a combination of supplementary items on the top of the sterilizer carriage with appropriate spacing between the items
  • Use of synthetic based & heavy wrapping materials can reduce the drying ability of the sterilizer particularly in relation to heaver instrumentation loads. If an SSD is considering changing it’s main wrapping material your AE (D) may need to be consulted to establish whether Performance Qualification testing is required in relation to the wrapping material & sterilizer as parameters may need to be changed.
  • Increasing use of plastic based sterilization trays & synthetic material for instrument composition should be eliminated where reasonable practical

The above issues can impact not just single packs of reusable devices, but entire batches, leading to the need for re-processing which impacts on device availability, cost, resource allocation & the ability to reprocess clinically required  urgent items.

Water Quality

Whilst steam is theoretically ‘clean’, the source of the water that produces the steam must be considered, as well as the materials and design of the steam generation and distribution systems. 

By using specific steam-to-steam generators that use a high quality water supply, typically Reverse Osmosis (RO), an HTM-compliant header or individual sterilizer steam generators, and a well-designed distribution system, steam quality can reach a dryness level above 95%, in line with BS EN 285. This also reduces the risk of introducing contaminants into the sterilisation process.

Find out more about AVM Services training and consultancy services to ensure that your AE(D) staff have all the requisite training and knowledge. Contact us on 01223 254499 or info@avm-addenbrookes.org.uk for more information.

Our Authorising Services

It might not be cost effective for you to employ permanant engineers for Quarterly and Annual audits. AVM employ a number of registered (IHEEM) AE(D)s and has been providing authorisation services to hospitals, medical centres and pharmaceutical companies for many years.

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Role of AE(D) Staff in driving Steam Quality