Define cleanliness requirements precisely
"Clean" or "particle-free" is not sufficient as a design basis. What matters is which requirements the customer defines for the part and how they are controlled throughout the process.
ISO Class 7 Cleanroom
Cleanroom Processes for Sensitive Plastic Parts
At BERGER, injection moulding itself takes place outside the cleanroom. Depending on requirements, moulded parts are either cleaned in a washer-disinfector or transferred into the cleanroom through a defined airlock process. Inspection, handling, assembly and packaging can then be carried out under ISO Class 7 conditions.
When a cleanroom process is appropriate
A cleanroom process is appropriate when plastic parts require further processing under controlled conditions after moulding – for example for particle-sensitive applications, sensitive functional surfaces, defined packaging requirements, cleanroom assembly or washer-disinfector cleaning followed by unloading on the clean side.
The room classification alone is not decisive; what matters is the controlled process around it. The required cleanliness state is defined first. Critical residues and particles, together with acceptable intermediate conditions, are then assessed. Finally, the packaging is specified to preserve the achieved condition through to handover.
Washer-disinfector, cleanroom and packaging as a process chain
The washer-disinfector is configured as a pass-through unit between the unclean and clean sides. Parts are loaded on the unclean side, cleaned in a defined cycle and unloaded on the clean side when the cycle is complete. They can therefore be transferred directly into the cleanroom area without returning to the unclean side.
If washer-disinfector cleaning is not required, the part can be transferred into the cleanroom through a defined airlock process. Depending on customer requirements, inspection, handling, assembly and packaging can then be carried out there. The exact sequence depends on the part, application and required condition at handover.
Ensuring cleanliness, documentation and repeatable production
To keep cleanroom processes repeatable in day-to-day production, BERGER defines the required procedures and equipment. Trained personnel, controlled airlock and handling procedures, and documented approvals complete the process.
BERGER treats the cleanroom, washer-disinfector and packaging as parts of one production and supply chain. The objective is a controlled transition from injection moulding through any required cleaning or airlock transfer to the processed and packaged unit.
Controlled interfaces in the cleanroom process
Define the cleaning route
Whether washer-disinfector cleaning is required or the parts can be transferred directly through the airlock without prior cleaning depends on the part, material, geometry and customer specification.
Control process interfaces
Critical points occur between production, cleaning or airlock transfer, the cleanroom, packaging and dispatch. These transitions must therefore be clearly defined, controlled and repeatable in production.
Prepare process equipment appropriately
The part is not the only factor. Trays, aids, tools, packaging and other process equipment must also be compatible with the required cleanliness state.
From the cleanliness target to controlled handover
The key is the required condition of the part at handover. Customer-defined cleanliness targets, any required washer-disinfector cleaning or controlled airlock transfer, together with handling, assembly, packaging and release, are combined into a reproducible process.
1
Define requirements and cleanliness target
BERGER clarifies the cleanliness requirements defined by the customer, assesses the critical process steps and determines which supporting documentation or approvals are required.
2
Define cleaning, airlock transfer and handling
BERGER determines whether parts are cleaned in the washer-disinfector and unloaded on the clean side, or transferred through the airlock without prior cleaning. Handling, inspection and, where applicable, assembly are then aligned with the required cleanliness state.
3
Control assembly, packaging and release
The individual process steps are controlled so that the part remains protected, is transferred under controlled conditions and, where required, can be released with documented evidence.
Cleanroom processes add value at the interfaces
The transfer points between the unclean and clean sides and between processing and packaging are particularly critical. At these interfaces, part condition, process equipment and packaging must be coordinated so that the achieved cleanliness level is maintained.
Questions about cleanroom, cleaning and packaging
When the agreed cleanliness, assembly or packaging requirements call for controlled further processing after injection moulding.
ISO Class 7 defines the cleanroom environment. In practice, it is equally important that washer-disinfector cleaning or controlled airlock transfer, personnel behaviour, equipment, handling, assembly, packaging and release are aligned with the customer-defined part requirements.
The washer-disinfector cleans suitable parts and process equipment and enables their direct transfer from the unclean to the clean side.
Yes. Depending on the project, inspection, handling, assembly and packaging can be carried out under controlled conditions in the ISO Class 7 cleanroom.
Parts whose agreed cleanliness, assembly or packaging requirements call for controlled conditions belong in the cleanroom. The specific transfer route is defined for each project.
