Disinfection aseptic areas

Internal fltlings snch as cupboards, drawers and shelves must be kept to a minimum. These may be made fiom stainless steel or a laminated plastic, which may be easily cleaned or disinfected bare wood is to be avoided, although painted or otherwise sealed woodwork m be satisfactory. Stainless steel trolleys can be used to transport eqiripmerrt and materials within the clean and aseptic areas but these must remain confined to then-respective units. Equipment should be so designed as to be easily cleaned and sterilized (or disinfected). 

Prior to the start of any production activity, materials and components must be transferred from a warehouse environment into a classified environment. For most items this will necessitate removal from boxes or cartons, transfer to a nonwooden pallet, and passage through an air lock which serves as the transfer system between the controlled and uncontrolled environments. Often components are contained within plastic bags within a box or carton, and in some cases there are multiple bag layers to facilitate disinfection and passage through air locks into different zones of operation within the aseptic area. The firm may utilize an external disinfection of the materials in conjunction with this transfer. The concern is for minimization of particles and bioburden on these as yet unprocessed items in order to protect the controlled environment. 

There are items that must be transferred into the aseptic processing area that cannot be treated within a sterilizer/oven. These include portable tanks, electronic equipment, and containers of sterile materials (ready-to-use items, sterile powders, environmental monitoring media, etc.). Air locks, pass-throughs, and similar designs are employed in which the exterior surfaces of the items are disinfected. The disinfection process may be completed by personnel outside and/or inside the aseptic area depending upon the specifics of the design. 

Interior surfaces (walls, floors and ceilings) shall be smooth and free from cracks they shall not shed matter and shall permit easy cleaning and disinfection. Drains should be avoided wherever possible and, unless essential, should be excluded from aseptic areas. Where installed they should be fitted with effective, easily cleanable traps and with breaks to prevent back-flow. The traps may contain electrically operated heating devices or other means for disinfection. Any floor channels should be open, shallow and easily cleanable and be connected to drains outside the area in a manner that prevents ingress of microbial contaminants. 

Electrical/mechanical systems for oral communication from and to aseptic areas should be designed and installed to permit effective cleaning and disinfection. 

To prevent the shedding or accumulation of dust and other particulate matter, ceilings, floors, and walls in the aseptic area, and floors and walls in the clean area, have smooth impervious surfaces that permit the repeated application of cleaning and disinfecting agents. 

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

Walls, floors, ceilings, and equipment in an aseptic area are cleaned and disinfected in accordance with a written program. The program differentiates between the daily cleaning and disinfection procedures and those undertaken when a different drug is fabricated. 

AH aseptic areas should be regularly disinfected in order that the number of microorganisms will be reduced to a minimum. The efficiency of UV lamps applied should be checked. 

As far as possible equipment should be designed and installed so that maintenance and repairs may be carried out without additional personnel having to enter the clean aseptic areas. If maintenance must be carried out within these areas,personnel concerned should receive appropriate training in the elements of microbiology. When within the areas they should be appropriately dressed, and use tools and equipment which have been sterilized as far as possible. Areas entered for maintenance should be cleaned and disinfected before processing recommences if the required standards of cleanliness and/or aseptic have not been maintained during the work. 

Dressing rooms and disinfecting facilities, for exclusive uses should be attached directly to the aseptic areas, and sterile garments should be provided. 

No obviously contaminated vessel should be opened. Rather it should be autoclaved immediately. If it is desired to test the nature of the contamination, a sample should be taken aseptically to avoid the spread of infection. This is best done at the end of the working day, and the work area then thoroughly disinfected and the UV lamp left on overnight. Contaminated dishes should be placed in special disposal bags (Sterilin Ltd.) before autoclaving, and often it is advisable to decontaminate the incubator by swabbing with disinfectant. 

Vacuum cleaners, however, are only suited to areas outside aseptic filling rooms because of their relative inefficiency of collection of smaller particles 11], leaving wet wiping with disinfectants as the standard method used for cleaning filling rooms. 

Liquid formulations should be prepared in an area that Is as clean as possible. Water for parenteral products should be of pharmacopoeial Water for Injection quality. Mixing vessels and other equipment should be cleaned and disinfected. It is normal for these areas to be provided with filtered air from HEPA fllteis of somewhat lower efficiencies than those providing protection to aseptic filling rooms. Sterilization of liquid products should be by filtration through... 

Disinfectants and Cleaning Processes Disinfectants are an integral part of cleaning processes for aseptic manufacture. They are usually purchased as con> centrated stock solutions for use they should be diluted in water of Purified Water or Water for Injection quality. They should be filtered into white areas, usually, because of their viscosity, through 0.4S pm sterilizing filters. Each diluted batch should be allocated a shelf-life, and different disinfectants should be used in documented rotation. 

Particle counters are not easily disinfected for taking into aseptic filling rooms. They may be dedicated to particular areas, or remote instruments with mobile or fixed sampling tubes can be purchased. 

Non-steriie products should not be processed in the same area and at the same time as sterile products. If non-steriie procedures are carried out in rooms normally designated as aseptic, these rooms must be suitably disinfected and flushed with filtered air. 

For Aseptic Processing where disinfection is employed to further reduce the surface contamination level, the choice of disinfectants and the way that they are used should be described in a procedure, in addition, detergents, disinfectants and antiseptics should be supplied sterile, or be sterile-filtered or otherwise sterilised at the use-dilution, or be sterilised as a concentrate and diluted only with sterile water. Diluted disinfectants or antiseptics should not be stored. Containers should not be topped up. Disinfectants/detergents used should be validated and approved. When disinfectants are used, more than one type should be employed. Monitoring should be undertaken regularly to detect the development of resistant stains. Disinfectants and detergents used in Class 1 and 2 areas should be sterilised prior to use. 

Clean, aseptic and other related processing areas should be cleaned frequently and thoroughly in accordance with a written program approved by the Quality Control Department. Where disinfectants are used, different types should be employed in rotation to discourage the development of resistant strains of micro-organisms. 

It is recommended that two people perform an aseptic work session [26]. One (the preparer) works in the Grade A zone and the other (the helper) carries out the disinfection and assists the preparer with getting materials to and from the working area. 

Murthough SM, Hiom SJ, Palmer M, Russel AD (2000) A survey of disinfectant use in hospital pharmacy aseptic preparation areas. Pharm J 264 446 8... 

The objective of transplantation is the introduction of an adequate amount of viable tumour tissue at a chosen site under aseptic conditions [12]. Hair is removed from all parts of the body of the donor and at the point of injection of the recipient, and the areas sterilised with disinfectant before transplantation is effected. Solid tumours are introduced subcutaneously or intramuscularly as tumour minces, cell suspensions or solid pieces, whilst ascitic tumours are introduced by intraperitoneal injection. From a large tumour it is usually possible to graft 30-100 animals, depending on the method of grafting and the type of tumour. 

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