Author: Vanessa 18 Mar. 2025 Category: Understanding Filtration
In a car painting workshop in Berlin, a group of Trenntech V8 filters triggered the intelligent early warning system due to abnormally high pressure difference. Engineers traced the real-time data and found that the pore uniformity of a batch of filter materials deviated by 0.3μm. This case revealed the core position of pressure difference test in quality control. As a “thermometer” of filtration performance, pressure difference test is not only related to product compliance, but also a technical passport for international market competition.
Ⅰ. Standardization battlefield of differential pressure test: equipment, methods and precision control
1. Strict definition of experimental conditions
Environmental benchmark:
- Temperature: (23±2)℃ (EN 1822) / (21±3)℃ (ASHRAE 52.2)
- Humidity: 50%±10% (European standard) / 45-55% (American standard)
Flow control:
- European standard EN 779: 0.944m³/min (34m³/h) rated air volume
- American standard ASHRAE 52.2: 1.02-1.53m/s face velocity
Test medium:
ISO 12103-1 A2 fine dust (European standard) / ASHRAE standard dust (American standard)
2.Precision Instrument Matrix
| Equipment type | European standard requirements | American standard requirements | Trenntech solution |
| Differential pressure sensor | Accuracy ±1Pa (0-500Pa range) | Accuracy ±0.1inH2O (≈±2.5Pa) | Swiss Keller PD-39X, ±0.5Pa |
| Particle counter | CPC ≥ 0.3μm resolution | Optical particle size classification ≥6 channels | Palas Promo® 5000+APS spectrometer |
| Wind tunnel device | Wind speed uniformity ≤ ±5% | Turbulence ≤3% | Self-designed laminar wind tunnel, uniformity ±2.1% |
| Data acquisition system | Sampling frequency ≥ 1Hz | Data storage ≥30 days | NI cDAQ-9189, 100Hz sampling + cloud storage |
Ⅱ. European Standard VS American Standard: Five Major Differences in Pressure Differential Test
1. Differences in Test Methods
Initial Pressure Differential Measurement:
- European Standard EN 1822: Take the value after stabilization for 10 minutes at rated air volume.
- American Standard IEST-RP-CC021: Three cycles of testing are required to take the average value.
Final resistance determination:
- European Standard: Reach 2 times the initial pressure differential or a specified final value (such as 450Pa for F7 filter material)
- American Standard: ASHRAE 52.2 is determined by the dust holding capacity increment curve
2. Energy Efficiency Evaluation System
- European Standard EN 1886: Introduces the concept of MPPS (most penetrating particle size), requiring the slope of the pressure differential-efficiency curve to be ≤0.15Pa⁻¹
- American Standard Energy Star: Incorporates the operating pressure differential into the TCO (total cost of ownership) calculation, requiring a five-year pressure differential increase of ≤120%
3.Differences in certification marks
| Index | European standard EN 1822 | American standard ASHRAE 52.2 | Trenntech dual-label certification |
| Pressure difference identification value | Initial pressure difference at rated air volume | Average pressure difference (initial + final)/2 | Dual-label parallel marking |
| Energy efficiency level | Grade A+ to E (EUROVENT) | MERV 1-20 | Simultaneous display of EUROVENT+MERV |
| Test cycle | 24-hour aging test | 6-stage incremental load test | 72-hour intensive testing |
Ⅲ. Trenntech‘s quality control pyramid
1. Material-level control
- Glass fiber diameter detection: 50 points are sampled per roll of filter material, and the diameter deviation is ≤0.15μm (SEM detection)
- Adhesive temperature resistance test: -40℃~120℃ cyclic impact 100 times without cracking (refer to DIN 53538)
2. Process-level monitoring
- Pressure difference online detection: automatic detection every 15 minutes on the production line, and automatic isolation of out-of-tolerance batches
- Digital twin system: reverse the filter material structure parameters through the pressure difference curve, with an accuracy of 92%
3. Finished product level verification
European standard compliance test:
- MPPS efficiency ≥99.95% (H13 level)
- Initial pressure difference ≤220Pa (@340m³/h)
American standard limit test:
- Pressure difference ≤350Pa under 30g/m² dust holding capacity
- Salt spray test 240 hours pressure difference fluctuation ≤5%
4. Intelligent traceability system
Each filter has a built-in RFID chip, which can be scanned to check:
- Raw material batch number and test report
- Production environment temperature and humidity record
- Full process differential pressure test curve
IV. Global compliance practice case
Ultra-clean challenge requirements of a Korean semiconductor factory: ISO 14644 Class 3 cleanliness; differential pressure fluctuation ≤ ±3Pa (for one consecutive year)
Trenntech solution: Nano-electret filter material + AI differential pressure compensation system; measured differential pressure fluctuation ±1.8Pa (365 days of continuous monitoring); Energy saving 23% to obtain LEED certification points.
At Trenntech, differential pressure testing has been upgraded from a quality control method to a gene editor for product design. Every 0.1Pa precision breakthrough is rewriting the international standards of the filtration industry-this may be the secret path for China’s manufacturing to move towards high-end.