What is ULPA ultra-high efficiency filter?

Let’s make one thing clear first: ULPA is not the name of a certain filter material, nor is it a fixed efficiency number. It is the first grade of high-efficiency filter and belongs to the same category as HEPA. The difference is that the proportion of particles allowed to penetrate under the specified test conditions is lower.

So when someone asks 'What is ULPA', the more accurate answer is: it is a type of terminal filter classified according to specific standards and used to control fine particles. Specifically, whether a certain product can be called U15 or U16 depends on what standard it is measured according to, what particle size it measures, and whether it measures the filter material or the complete machine. These three items are unclear, and just looking at the names is useless.

The relationship between it and HEPA is not 'who is more powerful'

HEPA and ULPA are often compared, but if the comparison is only focused on 'which one can filter smaller particles', the direction will be biased.

The filtration mechanism of both is the same - interception, inertial collision, diffusion, and the fiber or membrane medium is used to intercept particles. The difference is that under the same test method, the penetration ratio is different. ULPA requirements are lower, so they are more often considered in critical process locations.

But here's an easily overlooked point: higher levels don't automatically mean better performance in all aspects. Under the same size, the resistance of ULPA is often higher than that of HEPA, and the requirements for fan residual pressure are also higher. Whether the air supply volume is sufficient after installation is an account that must be calculated when selecting a model. For specific methods, please refer to the instructions related to the H13 upgrade. Therefore, between ULPA and HEPA, it is more of a question of 'is it enough?' rather than a question of 'which one is more advanced.'

What parts does it consist of

A finished ULPA product, taken apart, looks like this:

The filter material is the core, which is folded into pleats to form the filter surface. The material may be fiberglass or PTFE. The performance of the two is different under different working conditions. For details, please refer to the relevant instructions for filter material selection.

The outer frame provides structural support and is usually made of aluminum alloy or stainless steel. The selection depends on the environment and installation conditions.

The edge sealing glue sticks the filter material and the frame together. This is easily overlooked during model selection, but in high humidity or chemical environments, the colloid's tolerance directly affects long-term sealing reliability.

The sealing structure is the interface between the finished product and the installation frame. There are two methods: gasket or liquid tank. This part does not belong to the filter material itself, but it is the first place to be checked during on-site air leakage inspection.

Among these four pieces, the filter material determines the filtration efficiency, but whether the whole machine can achieve the desired effect, the other three pieces are equally critical.

The requirements vary depending on where it is installed.

The same ULPA is installed at the end of the ceiling and installed inside the equipment. There is a big difference in the things to be checked when selecting.

The end of the clean room serves the entire space, and the focus is on air volume distribution, matching with the air conditioning system, and interchangeability during mass installation.

Device-side applications such as For EFU equipment-side fan filter units , the situation is much more complicated. The internal space of the equipment is often determined during the mechanical design stage. Whether the filter element can be installed and whether it can be taken out when changing the filter element is sometimes more critical than the filtration level. installed in the FFU fan filter unit , the filter element resistance and the unit fan operating point must be checked together. For the ULPA on

Being of the same grade does not mean that these interfaces are interchangeable. For specific product selection conditions, please refer to Description of ULPA Ultra High Efficiency Filter .

Several common pitfalls when selecting models

Only the grade is reported, not the test conditions. 'Require U15' This sentence itself is not informative enough. It also needs to explain what standard is used and what particle size is measured. Grade marks under different standards are not directly interchangeable.

Use the filter material report as the complete machine report. The filter material test is the material itself, and the whole machine also needs to be tested for folding, edge sealing and assembly. These two types of reports correspond to different acceptance links.

Ignore sealing and installation. No matter how efficient it is, air leakage from the interface will be bypassed. Product testing, installation leak detection and clean area particle testing are three things that must be done and recorded separately.

Reverse the filter element level according to the room level. The cleanliness level describes the particle concentration in the space, and the ULPA level describes the product penetration performance, separated by air supply volume, airflow organization and operation management. The two cannot be directly converted.

Selection and Acceptance Checklist

About Aili Industrial’s ULPA package

The problem often encountered in ULPA selection is not the product itself, but the mismatch between the product and other links: the resistance of the filter element exceeds the fan capacity, the sealing structure does not match the installation frame, and the size can be installed but cannot be replaced.

Aili Industrial's manufacturing system covers filters, motors, fans, control systems, sheet metal and complete machine assembly. This means that ULPA can be combined with FFU fan filter unit、The EFU equipment-end fan filter unit is checked under the same project conditions. The filter element resistance and fan working point can be calculated together at the planning stage, instead of separately purchasing and then finding problems on site.

When enquiring, provide specific working conditions, size interfaces, target air volume and testing requirements to help determine the appropriate configuration. Actual performance is based on confirmed model information and test results.