Clean room design Flashcards
why is aseptic manufacturing more demanding
there is no final sterilisation step
where are most sterile manufacturing processes performed
in clean rooms
give examples of sources of contamination
bacteria, fungi, viruses
from skin, wounds, cleaning materials, packaging, poor disinfection, poor hygiene
what are clean rooms
self contained facilities with dedicated ventilation systems
- control air quality, temperature and humidity
how is air filtered in a clean room
air filtered by High efficiency particulate air (HEPA) filters
describe the air handling in clean rooms
- dirty air from the surrounding area is prevented from entering the clean room by controlling air pressure
- cleanest room at highest (positive) pressure
- air flows from the cleanest to dirtiest areas
name the 2 categories clean rooms fall under in terms of air flow
unidirectional and non unidirectional
how is airflow controlled in a unidirectional clean room
- normally have vertical airflow- air flows downwards through HEPA filters located in ceiling
- air is extracted through perforated flooring or grilles mounted at floor level
how is airflow controlled in a non unidirectional clean room
- air flows from HEPA filters located in various positions and returned through opposite locations
- air flow may be turbulent in nature
describe the internal room design of a clean room
- floors, walls and ceilings should be made of a smooth, impervious material and rounded corners
- all doors should be controlled to prevent unwanted flow of air from one area to another
- there should be no shelves, window ledges or door frames
- there should be no water sources, sinks or drains
describe the features that should be found in the wash room
- hand washing facilities should be available external to changing rooms
- taps should be elbow or foot operated
what are particle loads
- highest standards of environmental control are included in the design of clean rooms
- there are a maximum number of particles allowed in clean rooms at rest and during operation
give an example of a clean room Grade A
Laminar flow cabinets and isolators
give an example of a clean room grade B
the aseptic room
give an example of a clean room grade C
the preparation room
give an example of a clean room grade D
support rooms
what is work zone 1
area where aseptic preparation is actually carried out
- laminar air flow cabinets are used during aseptic processing to protect products from contamination
what is work zone 2
- horizontal laminar flow- filters are at the back of units and air streams over the critical zone towards the operator
- vertical laminar flow- filters are above the work surface and force clean air downwards in parallel streams
what is work zone 3
- isolators are a clean environment in themselves and should also be sited within a clean room
- isolators act as a physical barrier between the product and the operator
what is work zone 4
- most commonly used isolators are either positive pressure or negative pressure isolators
- positive pressure protects product and operator
- negative pressure gives a greater operator protection, but less protection for the product
outline ways of contamination control
- personal hygiene- hand washing
- general hygiene- outside shoes shouldn’t be brought into a clean room
- only approved clean room clothing is allowed - cleaning and disinfecting- typical cleaning schedule
- horizontal surfaces attract more contamination than vertical ones
- lower surfaces attract more contamination than higher ones
- cleaning should occur at end of working day
