This page contains questions relating to the facilities for Dental Decontamination.

Should we use central or local decontamination facilities?

The preferred option for decontamination is through an accredited central decontamination unit. However, it is recognised that is rately a viable option for a range of reasons including available CDU capacity. Nevertheless this option should be investigated on an individual NHS Board basis as part of a detailed option appraisal. In many cases, he provision of a local decontamination unit (LDU) is the only option. This should only be pursued if the considerable initial and ongoing responsibilities and costs are fully understood and acceptable, and if a compliant facility can be provided.

Why do we need a separate room to clean instruments?

Segregation of the decontamination process from areas of clinical activity prevents reprocessed instruments being exposed to any contamination generated during patient treatment e.g. aerosols created by high speed drills. It reduces the risk of accidental re-use of contaminated instruments and minimizes the exposure of patients and staff to any contamination generated during the decontamination process.

What is the risk of transmitting infection to a patient whilst cleaning instruments in the surgery?

If instruments are cleaned in the surgery, there is a risk that dirty and clean instruments will be mixed up and that clean instruments may become contaminated via aerosols generated during the instrument cleaning process.

Both of these risks are reduced by removing the decontamination process to a separate room (though the risk of cross infection via aerosols generated during treatment remains).

Decontamination within a separate dedicated local decontamination unit enables the process to be better managed by following a dirty to clean workflow and preferably physical segregation of clean and dirty processes. This has the added benefit of removing the noise and heat associated with the process from the clinical area.

What size of facility do we need?

The size of a LDU depends on how many surgeries will use the facility, how many instruments will be processed and how many pieces of decontamination equipment will be required. This needs to be worked out for each individual setting. Guidance can be found in Scottish Health Planning Note 13 Part 2 Decontamination Facilities – Local Decontamination Units (see www.scottishdental.org/index.aspx?o=2136) and advice can be sought from NHS Boards via Dental Practice Advisors.

Why are two rooms the preferred option for a decontamination facility?

Having a room for dirty instruments to be cleaned and a separate room that deals only with cleaned instruments and the sterilization process: prevents recontamination of cleaned/sterilized/sterile devices from other processes e.g. cleaning; reduces the risk of mixing up dirty and clean instrument or of clean instruments being recontaminated through contact with unclean instruments.

Why do we need a cleaning and rinsing sink if we are moving away from manual to automated processing, particularly if space is a problem?

Even when using an automated system, there are likely to be some instruments that cannot be cleaned in this manner. Therefore, manual cleaning is required for these instruments and for occasions when the automated system is unavailable. The preferred method for manual cleaning involves the use of two sinks, one for cleaning and one for rinsing, or a sink and a basin as a short term temporary measure.

Does the decontamination room need to have a hand hygiene sink?

Yes. Having a hand hygiene sink in the LDU enables it to be readily available and used exclusively for the routine hand washing required when processing instruments through decontamination (before instrument cleaning and between the dirty and clean processes).

What are the ventilation requirements for a single room local decontamination unit?

To reduce the possible recontamination of instruments the preferred direction of air flow is from the “clean” area to the “dirty” area. When installing ventilation equipment consideration should be given to the heat and steam generated by the decontamination equipment used. An extraction fan sited above the “dirty” area will help provide the correct direction of air movement and assist in providing a comfortable working environment for staff. The use of freestanding or ceiling-mounted fan units is not recommended.

If I have two practices, one with an LDU and the other without, can I transport my instruments a short distance between practices?

Yes. The way the instruments are transported must comply with Carriage of Dangerous Goods Regulations. A guide to these regulations with respect soiled instruments is available at