Dean areas

For sterile Filtration of ophthalmics and small-volume parenteral products it is not unusual to Find several Filters mounted in series. For instance a compounded bulk product may be Filtered through the wall from a dean area into an aseptic filling room. In these cases there are usually two filters mounted in... 

Personnel working in areas where contamination is a hazard, e.g., dean areas or areas where highly active, toxic, infectious, or sensitizing materials are handled, should be given specific training. 

The production of sterile preparations should be carried out in dean areas, entry to which should be through airlocks for personnel and/or for goods. Clean areas should be maintained to an appropriate standard of deanliness and supplied with air that has passed through filters of an appropriate efficiency. 

Only the minimum number of personnel required should be present in dean areas this is particularly important during aseptic processes. Inspections and controls should be conducted from outside the areas as far as possible. 

Wrist-watches and jewellery should not be worn in dean areas, and cosmetics that can shed partides should not be used. 

Grade D The hair and, where appropriate, beard should be covered. Protective dothing and appropriate shoes or overshoes should be worn. Appropriate measures should be taken to avoid any contamination coming from outside the dean area. 

In dean areas, all exposed surfaces should be smooth, impervious, and unbroken in order to minimize the shedding or accumulation of partides or microorganisms and to permit the repeated application of deaning agents and disinfectants, where used. 

A filtered air supply should maintain a positive pressure relative to surrounding areas under ail operational conditions and flush the area effectively. Moreover, particular attention should be paid to the protection of the zone of greatest risk, that is, the immediate environment to which the product and the cleaned components in contact with it are exposed. The various recommendations regarding air supplies and pressure differentials may need to be modified if it becomes necessary to contain materials such as pathogenic, highly toxic, radioactive, or live viral or bacterial materials. Decontamination faalities and the treatment of air leaving a dean area may be necessary for some operations. 

A conveyor belt should not pass through a partition between a dean area 6 and a processing area of lower air cleanliness, unless the belt itself is continuously sterilized (e.g., in a sterilizing tunnel). 

As far as possible, equipment fittings and services should designed and installed so that operations, maintenance, and repairs can be carried out outside the dean area. Equipment that has to be taken apart for maintenance should be resterilized after complete reassembly wherever possible. 

When equipment maintenance is carried out within the dean area dean instruments and tools should be used, and the area should be deaned and disinfected where appropriate before processing recommences, if the required standards of deanliness and/or asepsis have not been maintained during the maintenance work. 

Fumigation of dean areas may be useful for redudng microbiological contamination in inaccessible places. 

Activities in dean areas, especially when aseptic operations are in progress, should be kept to a minimum, and the movement of personnel should be controlled and methodical, to avoid excessive shedding of partides and organisms due to over-vigorous activity. The ambient temperature and humidity should not be uncomfortably high because of the nature of the garments worn. 

The presence of containers and materials liable to generate fibres should be minimized in dean areas and avoided completely when aseptic work is in progress. Components, bulk-product containers, and equipment should be handled after the final deaning process in such a way that they are not recontaminated. The stage of processing of components, bulk-product containers, and equipment should be properly identified. 

The presence of containers and materials Sable to generate fibres should be minimized in dean areas and avoided completely when aseptic work is in progress. 

CLEAN/CONTAINED AREA An area constructed and operated in such a manner that will achieve the aims of both a dean area and a contained area at the same time. 

Changing and washing should follow a written procedure designed to minimise contamination of dean area dothing or carry-through of contaminants to the dean areas. 

The sanitation of dean areas is particularly important They should be deaned thoroughly in accordance with a written programme. Where disinfectants are used, more than one type should be employed. Monitoring should be undertaken regularly in order to detect the development of resistant strains. 

Containers and materials liable to generate fibres should be minimised in dean areas. 

Unloading freeze driers contaminates the immediate environment. Therefore, for single-ended freeze driers, the clean room should be decontaminated before a further manufacturing batch is introduced into the area, unless this contains the same organisms, and double door freeze driers should be sterilized after each cycle unless opened in a dean area. 

Sterile products must be processed in a specific area which is specially equipped and maintained to ensure cleanliness and sterility of the area. Sterile products which do not require processing under aseptic condition and which will undergo terminal sterilization may be processed in a nonsteriie but dean area. 

The various operations of component preparation, produd preparation and filling should be carried out in separate areas within the dean area... 

Recommended limits for microbiologcal monitoring of dean areas in operation. 

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