High-efficiency air filters are critical in industries such as pharmaceuticals, semiconductors, and cleanrooms. To ensure their performance, the most widely used standard in Europe is EN 1822.
This article explains EN 1822 in a clear and practical way, including its classification system, testing methods, and real-world applications.
1. What Is EN 1822?
EN 1822 is a European standard used to evaluate the performance of HEPA and ULPA filters.
It focuses on:
- Filtration efficiency
- Leak detection
- Most Penetrating Particle Size (MPPS)
👉 The goal is to ensure filters meet strict requirements for high-cleanliness environments.
2. EN 1822 Classification System
EN 1822 classifies filters based on their efficiency at MPPS:
| Class | Efficiency |
|---|---|
| E10 | ≥ 85% |
| E11 | ≥ 95% |
| E12 | ≥ 99.5% |
| H13 | ≥ 99.95% |
| H14 | ≥ 99.995% |
| U15–U17 | ≥ 99.9995% and above |
👉 HEPA filters typically fall into H13–H14 classes
👉 ULPA filters go beyond H14
3. Key Concept: MPPS
The Most Penetrating Particle Size (MPPS) is the particle size that is hardest to capture.
- Typically around 0.1–0.3 μm
- Efficiency is lowest at this size
👉 EN 1822 evaluates filters at MPPS to ensure worst-case performance
4. EN 1822 Testing Process
The EN 1822 standard includes several test steps:
Step 1: Determination of MPPS
- Measure efficiency across particle sizes
- Identify the weakest filtration point
Step 2: Overall Efficiency Test
- Evaluate filter efficiency at MPPS
Step 3: Leak Test (Scan Test)
This is the most critical step.
- The filter surface is scanned
- Local leaks are detected
- Ensures no weak points
👉 Even if overall efficiency is high, a local leak can cause failure
5. Why Leak Testing Is Critical
Unlike general ventilation filters, HEPA filters must:
✔ Provide uniform performance
✔ Have no local defects
✔ Meet strict cleanroom requirements
👉 A single leak can compromise the entire system
6. EN 1822 vs Other Standards
Compared to ISO 16890:
- EN 1822 → High-efficiency filters (HEPA/ULPA)
- ISO 16890 → General ventilation filters
👉 EN 1822 is much stricter and more detailed
7. Applications of EN 1822 Filters
EN 1822-tested filters are widely used in:
- Pharmaceutical cleanrooms
- Semiconductor manufacturing
- Hospitals and healthcare facilities
- Aerospace and precision industries
👉 These applications require extremely clean air
8. Challenges in EN 1822 Testing
In practice, testing HEPA filters can be challenging:
- Detecting very small leaks
- Maintaining stable aerosol concentration
- Ensuring scanning accuracy
- Avoiding false results
👉 These challenges require specialized testing equipment
9. Recommended Testing Solution
For accurate EN 1822 testing, especially leak detection, professional equipment is essential.
The SC-L8023 Scanning Filter Tester from SCPUR is designed specifically for HEPA/ULPA filter testing.
Key Advantages
- High-sensitivity leak detection
- Precise scanning system
- Stable aerosol generation
- Reliable and repeatable results
👉 Ensures compliance with EN 1822 requirements
10. Conclusion
EN 1822 is a critical standard for evaluating HEPA and ULPA filters, ensuring both:
✔ High overall efficiency
✔ Zero local leakage
Understanding this standard is essential for manufacturers and users in high-cleanliness industries.










