Why Filter Efficiency Matters
In commercial HVAC systems, primary filters serve as the first line of defense, capturing 85%+ of airborne particulates above 5μm. Our ISO 16890-certified testing demonstrates how G3/G4 filter selection impacts operational efficiency and maintenance costs.
1. Understanding Efficiency Classifications
1.1 ASHRAE vs. ISO Testing Methods
- ASHRAE 52.2 MERV: G3 ≈ MERV 6 | G4 ≈ MERV 8 (PM1-PM10 scale)
- ISO 16890 Reporting: G3 = ePM10 50% | G4 = ePM10 70%
Note: Dual labeling (MERV + ISO) is recommended for North American markets
1.2 Key Performance Metrics
| Parameter | G3 Filter | G4 Filter |
|---|---|---|
| Arrestance (ASHRAE) | 65-80% | 80-90% |
| Initial Pressure Drop | ≤0.28 in.w.g. (70Pa) | ≤0.32 in.w.g. (80Pa) |
| Dust Holding Capacity | 14-18 oz/yd² | 18-22 oz/yd² |
2. Application-Specific Recommendations
Ideal G3 Applications:
✔️ Retail store rooftop units (RTUs)
✔️ Warehouse ventilation pre-filtration
✔️ School HVAC systems (ANSI/ASHRAE 62.1 compliant)
When to Choose G4:
✔️ Hospital patient rooms (FGI Guidelines compliance)
✔️ Data center AHUs (ASHRAE TC9.9 compatible)
✔️ Manufacturing facilities requiring OSHA PEL compliance
3. Engineering Innovations
Our American-market optimized filters feature:
- Dual-Stage Filtration: Outer synthetic fiber layer (100% PP) for large particulates + inner electrostatic media for fine particle capture
- Corrosion-Resistant Frames: 20GA galvanized steel meeting ASTM A653 SS Grade 33 specifications
4. Total Cost of Ownership Analysis (NREL Model)**
5-year ROI when upgrading from G3 to G4:
| Facility Type | Energy Savings | Filter Replacement Savings | Labor Reduction |
|---|---|---|---|
| Office Buildings | 12% | $380/year | 22 hours |
| Research Labs | 18% | $620/year | 35 hours |