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Pharmaceutical production is strictly regulated around the world where contamination could have severe consequences .
Fume extractor air and pressurisation air quantities change the cooling and heating capacities as well as supply air quantities . Some extract canopies require a separate air supply for short circulating outside air to extract air . The resulting performance required from the HVAC system inevitably requires rather unusual coil selections and sometimes creative methods of achieving that performance is required .
Cascading and pressure drops in the cleanrooms also affect fan selection . A materials lab may require positive and negative spaces adjacent to one another as they could use aggressive acids that cannot tolerate possible contamination from the outside . It does occur that different spaces such as this are fed from the same unit . Fans selection must frequently have high static pressures available in order to allow for the rooms to be cascaded . Sometimes the fan curves from conventional plug fans are not adequate and a custom-built fan is required . Occasionally the motors may have to be fitted outside air handling unit casings . Fortunately , direct drive fans have replaced the old belt driven units as belts actually shed quite a bit of debris themselves .
Cleanrooms in agricultural research are also vital in the production and development of seeds , pesticides , feed , and other products that help produce food around the world . Some agricultural cleanrooms however are not used for research purposes , but for growing plants . These types of facilities cater to highly controlled growing environments that are free from pests , cross pollination , spores , and other opportunistic pathogenic contaminations . Another interesting factor with these agricultural growing cleanrooms is that they may even be required to meet ISO Class 5 levels – far cleaner than you would expect . A cleanroom environment in this setting is also required for the protection of occupants that may be exposed to harmful and deadly spores produced by the crop within the space , or chemical reactions with skin , as another example , that over time can cause various other health-related outcomes ( irritation to loss of nerve function and sensations ).
Some other less common applications may even require extremely precise accuracy , down to parts per billion rather than million . These applications require far more sophisticated AHUs that may also be required to be made out of a particular material - such as polypropylene . The reason for this could be the reactive nature of the processes involved within the space .
Achieving the required cleanroom status is relatively easy for commissioning and handover , however the overall design must take into account maintaining that status day after day , which in turn requires further considerations than just the HVAC . These include processes such as room flushing , wall , floor , and ceiling cleaning to name a few .
GMP AS THE FOUNDATION FOR DESIGN METHODOLOGY IN PROCESSING PLANTS The World Health Organisation ( WHO ) has established detailed guidelines for good manufacturing practice ( GMP ) although many countries have formulated their own requirements for GMP , based on these guidelines .
GMP is an international system for ensuring that products are consistently produced and controlled according to set quality
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RACA Journal I March 2022 www . hvacronline . co . za