What tests should be done after ULPA replacement or upgrade? System integrity and performance verification

ULPA filter replacement or upgrade should be determined according to the scope of the change, usually focusing on installation integrity, air volume, pressure difference and related process area performance. Testing after Upgrades should also recheck fan and system capabilities. The test items for replacement and upgrade of the same model are not the same. Using the same list to cover all changes will either waste time by testing too much, or leave hidden dangers if the test is missed. Aili Industries has a corresponding verification framework for different types of changes in product change management: replacement of the same model looks at interfaces and seals, grade changes look at resistance and working points, and structural modification looks at system rebalancing. This framework can assist the project team in defining the scope of testing.

1. List the actual changed items: first distinguish the type of change

Distinguish between replacement of the same model, changes in filter material or grade, changes in sealing structure, and box modifications. Different changes cannot directly use the same test list.

Replacement of the same model mainly involves installation status and sealing; grade changes will also change resistance and working points; changes in sealing structure require re-confirmation of leak detection methods; box modifications may affect airflow distribution. Aili Industry isWhen the HEPA/ULPA filter selection is changed, the items that need to be re-confirmed will be described according to the type of change to prevent the project party from covering the new configuration with old test reports. The relationship between levels and filtering requirements can be found inISO cleanliness level comparison。

2. Restoring comparable working conditions: test data must have reference

Record the rotation speed, operating mode and test air volume, measure the baseline of the new filter element, and verify affected indicators such as uniformity and room pressure if necessary.

The working conditions before and after replacement are inconsistent, and the data cannot be compared. Ai Li industrialThe FFU computer group control system can record the partition operating parameters before replacement and retest with the same settings after replacement, making it easy to determine whether changes in air volume and pressure difference are due to filter elements or system adjustments. Device-side projects can passThe operation records of the fan filter unit at the EFU equipment end establish comparable working conditions.

3. Correspond conclusions to changes: the report must be able to answer 'what was changed this time'

Save old and new models, numbers and reports to identify which performance has been verified. Just relying on the new filter element certificate cannot prove that the modified machine has achieved the original goal.

If the changed report only says 'Leak detection passed', it cannot explain whether the air volume, pressure difference and regional performance are affected. Aili Industry isWhen the ULPA ultra-high-efficiency filter is delivered, the test data of the new filter element and the model change can be compared to facilitate the project party to match the performance data of the new configuration with the change content. Please refer to the key points for verification of sealing and integrity.HEPA FAQs and Selection Guide。

4. Level upgrade requires rechecking the fan and system capabilities.

If the air volume drops after upgrading H14 to ULPA, the fan and resistance should be rematched instead of just doing a new particle count. An increase in level is usually accompanied by an increase in resistance. The original fan may have insufficient residual pressure at the target air volume, and speed adjustment compensation or configuration adjustment needs to be confirmed.

Aili Industry isIn the non-standard ULPA filter upgrade project, the target air volume and the original fan curve can be combined to evaluate whether the upgraded working point meets the requirements to avoid the situation of 'the level is upgraded but the air volume does not meet the standard'. Ceiling projects can be combinedCheck the fan configuration of the FFU fan filter unit .

5. Related questions and answers

Does replacement of the same model also need to be tested?
The on-site installation status has changed and should be confirmed after completing the replacement required by the project. You cannot just continue to use the old report. The test for replacement of the same model focuses on installation integrity and sealing, not filtration performance.

Is it enough to just do a leak check after replacement?
Depends on the type of change. Replacement of the same model usually focuses on installation integrity. Changes in grade also require checking the air volume, pressure difference and system operating point.

After upgrading ULPA, the air volume drops. Should I perform a supplementary test or deal with the air volume first?
You should first confirm whether the fan operating point is satisfied. When the air volume is insufficient, supplementary particle counting has limited significance, and the system matching problem should be solved first.

6. Related articles

ULPA ultra-high efficiency filter FAQ and selection guide

HEPA FAQs and Selection Guide

FFU FAQ and technical support

EFU FAQ and technical support

7. Key points for selection and acceptance inspection

8. Product matching and technical support from Aili Industrial

Aili Industry isWhen the HEPA/ULPA filter selection is changed, the items that need to be re-confirmed are explained according to the type of change.The delivery of ULPA ultra-high-efficiency filters can be matched with the provision of new filter element testing data and model changes to facilitate matching performance data with changes.The FFU computer group control system can record partition operating parameters before and after replacement, making it easy to determine the source of changes;Non-standard ULPA filter upgrade projects can be combined with the original fan curve to evaluate the working point.The FFU fan filter unit can check the fan configuration, and the equipment-side projects can be combinedof the fan filter unit at the EFU equipment end . Confirm the operation record Provide process objectives, installation drawings, operating conditions and acceptance requirements, and can further communicate ULPA standard specifications, non-standard interfaces, samples and batch matching. The specific parameters and test range are based on the confirmed model and technical documents.