What Is PAO Testing and How Does KOWA Perform and Report It?
✅ Comprehensive PAO Testing for HEPA/ULPA Filter Integrity in Critical Environments
KOWA provides professional PAO testing services for cleanrooms in the biotechnology, pharmaceutical, and medical industries. PAO testing is a vital procedure used to verify the integrity of HEPA and ULPA filters by detecting potential leaks and ensuring compliance with cleanroom standards.
Testing Procedure:
🔬 What Is PAO Testing?
PAO (Polyalphaolefin) testing is an aerosol-based leak detection method used for filter integrity testing in cleanroom environments. This method uses a PAO aerosol generator and a photometer to detect the presence of leaks in high-efficiency air filters.
How It Works:
PAO aerosol is injected upstream of the air filter.
A photometer measures downstream concentrations of aerosol particles.
By comparing the upstream and downstream particle concentrations, the filter's efficiency and any leaks are identified.
Reporting:
🧪 Step-by-Step PAO Testing Procedure
System Preparation
Ensure the HVAC or air handling unit is operating normally.
Adjust airflow to a stable, balanced condition.
Introduce PAO aerosol to the upstream side of the filter.
Upstream Concentration Measurement
Use an aerosol photometer to confirm upstream particle concentration.
Target concentration: 10–20 µg/L of air.
Leak Detection Scan
Perform a systematic scan of the filter media and its frame.
Use a photometer probe to identify any drop in filtration performance.
Scanning Methods
Use zigzag or edge-to-center patterns for full surface coverage.
Focus on filter frames and ceiling grid interfaces for leak-prone areas.
Maintain a probe distance of ~25mm and a movement speed of 50mm/sec.
Leak Identification Criteria
If downstream reading > 0.01%, a leak is suspected.
Re-test the spot after moving 100mm back.
Persistent readings indicate a confirmed leak requiring repair or replacement.
Filter Efficiency Formula:
Filter Efficiency (%) = (1 - Penetration Rate) × 100%
📄 How Is the PAO Test Report Delivered?
After completing the PAO test, KOWA provides a detailed report including:
Upstream PAO concentration values
Downstream leakage rate
Scan results of each filter and frame
Identified leak locations (if applicable)
Report Turnaround Time:
Delivered within 5–10 working days after testing
Excludes additional time if airflow volume or velocity testing is required
💡 Why Choose KOWA for PAO Testing?
✔️ Experienced in cleanroom environments (Class 100–10000)
🔬 Advanced PAO aerosol generation and detection equipment
📈 Accurate, regulatory-compliant test procedures
📝 Clear and actionable reports for certification or internal use