How to control secondary pollution when replacing ULPA? Process area protection and packaging management

ULPA filter replacement should cover disassembly of old parts, protection of openings, transfer of new parts and post-operation cleaning. Secondary pollution control during Contamination can come from dust accumulation, packaging materials, personnel and exposed interfaces. During the replacement process, the dust carried by the old parts and the packaging materials themselves may become sources of pollution, and the control point is not just the filter element. Aili Industrial takes this as design input in product packaging design: packaging material selection, internal and external layered structure, and unpacking sequence are all determined based on the idea of ​​reducing dust during unpacking and preventing outer packaging from entering the clean area, so that secondary pollution control has corresponding structural support during the unpacking process.

1. Protect the process area first, then touch the old parts

Remove or cover sensitive workpieces, divide areas for clean and unprocessed items, and arrange cleaning tools and packaging routes to prevent old filter elements from passing through unprotected workstations.

Protective actions must be completed before disassembly begins. Sensitive workpieces inside equipment or above workstations may accumulate dust and packaging debris and fall to the surface once exposed throughout the changeover process. Aili Industry isThe relative relationship between the exit direction of old parts and the position of the workpiece will be considered in the design of the maintenance conditions of the fan filter unit at the EFU equipment end , so as to facilitate on-site judgment in advance which areas need to be covered and which paths need to be avoided. The relationship between levels and filtering requirements can be found inISO cleanliness level comparison。

2. Separate management of dismantling the old and assembling the new, and the packaging must be able to cooperate with this process.

The old parts should be packaged as soon as possible according to the on-site requirements, and dust should not be shaken next to the new filter element. Unpack new parts at the appropriate location to prevent contamination from the outer packaging from entering the installation surface.

If the packaging of old parts and the unpacking of new parts are mixed in the same area, dust can easily fall on the new parts that have been unpacked. Aili Industry isHEPA/ULPA filter packaging adopts a layered structure of outer packaging and clean inner packaging: the outer packaging is removed in the buffer zone, and the inner packaging is opened when it is close to the installation position to reduce the amount of attachments from the outer packaging being brought into the clean area. The packaging material itself is also selected according to low dust generation requirements to reduce debris generated by the unpacking action. The purpose of this layered design is to allow 'removal of the old' and 'installation of the new' to be physically separated. The packaging package for old parts can be provided together with the delivery.Large-size models of non-standard ULPA filters can be configured with corresponding packaging methods according to size.

3. Complete cleaning and re-inspection. Process control cannot be remedied by results.

Clean seal contact surfaces, debris and tools, and verify installation integrity and related environmental performance after structural restoration. Do not use test results as a substitute for process controls.

Passing the leak test after replacement does not mean that no contamination spread during the process. Debris from the seal contact surface, tool residue, and packaging fragments may remain in the clean area after the leak test has passed. Aili Industrial has clear process requirements for sealing surface cleaning, tool management and debris control during the entire machine assembly process. This set of requirements can be converted into cleaning inspection items for on-site replacement operations: sealing surface cleaning, debris collection, tool inventory, and the structure will be restored after each item is confirmed. The relationship between sealing surface cleaning and leak detection can be referred toHEPA FAQs and Selection Guide。

4. When the removed filter element is located above precision equipment, the access method must be determined in advance.

When the disassembled filter element is located above the precision platform, the platform should be protected first and the way to pick up old parts should be planned to prevent dust from falling into the process area during disassembly.

The receiving method includes receiving tooling, sealing bag position and personnel position. Aili Industry isthe FFU fan filter unit will indicate the exit direction of the filter element, making it easier to arrange the pick-up route on site; the packaging method of the matching old parts can be explained at the time of delivery to avoid finding a temporary container at the moment of disassembly. The detachable structural design of Please refer to the key points of the replacement process and packaging.ULPA ultra-high efficiency filter FAQ and selection guide。

5. Related questions and answers

Can the old filter element be left exposed for a while?
It should be packaged and transferred as required based on the nature of the pollution to prevent dust from spreading to the work area again. Leaving it exposed temporarily will allow the dust that has been controlled during disassembly to spread again.

Can outer packaging be brought into the clean area?
It is recommended to remove it in the buffer zone. There are many particles attached to the outer packaging during transportation and handling, and bringing them into the clean area will increase the source of pollution.

Does the leak detection process still need to be inspected for cleanliness?
need. Leak detection verifies seal integrity, while process cleaning involves debris, tools and packaging residues. The two are control items at different levels.

6. Related articles

ULPA ultra-high efficiency filter FAQ and selection guide

HEPA FAQs and Selection Guide

EFU FAQ and technical support

FFU FAQ and technical support

7. Key points for selection and acceptance inspection

8. Product matching and technical support from Aili Industrial

Aili Industry isThe HEPA/ULPA filter packaging design adopts a layered structure of outer packaging and clean inner packaging. The packaging materials are selected according to low dust generation requirements, which facilitates the physical separation of old parts and new ones on site. Packaging packages for old parts can be provided at the time of delivery.of the EFU equipment end fan filter unit, the relative relationship between the exit direction of the old parts and the position of the workpiece is considered.When designing the maintenance conditions the FFU fan filter unit indicates the exit direction for easy arrangement of access routes. The detachable structure of The process requirements for sealing surface cleaning, tool management and debris control in the entire machine assembly process can be converted into cleaning inspection items for on-site replacement operations.Large-size models of non-standard ULPA filters can be configured with packaging methods according to size. Provide process objectives, installation drawings, operating conditions and acceptance requirements for further communicationULPA ultra-high efficiency filters . Standard specifications, non-standard interfaces, samples and batch matching of The specific parameters and test range are based on the confirmed model and technical documents.