Air Filters for Cleanrooms

1. ‌Types of Filters and Their Functions‌

• ‌HEPA/ULPA Filters‌: HEPA filters capture particles ≥0.3 μm with 99.99% efficiency, while ULPA filters target particles ≥0.12 μm with 99.999% efficiency. They are typically installed at the air supply terminal.
• ‌Pre-Filters (Primary/Medium Efficiency)‌: Primary filters remove particles ≥5 μm, and medium filters handle 1–5 μm particles, protecting HEPA/ULPA filters and extending their lifespan.
• ‌FFU (Fan Filter Unit)‌: Integrated units combining fans and HEPA filters, enabling modular cleanroom design.

2. ‌Working Principle‌

• ‌Mechanical Filtration‌: Multi-layer filter media (e.g., fiberglass) progressively capture particles.
• ‌Negative Pressure Adsorption‌: Fans create negative pressure zones to draw in and filter contaminated air.
• ‌Smart Control‌: Modern systems adjust airflow automatically to meet varying cleanliness requirements.

3. ‌Applications‌

• ‌Industrial Cleanrooms‌: Semiconductor manufacturing requires Class 10 cleanliness (≤10 particles ≥0.1 μm per cubic meter), relying on HEPA/ULPA filters.
• ‌Pharmaceutical/Electronics Industries‌: necessitate integrated cleanroom HVAC systems, air showers, and positive-pressure environments.

4. ‌Maintenance Guidelines‌

• ‌Regular Replacement‌: Replace pre-filters when pressure drop doubles; HEPA filters every 1–2 years.
• ‌Environmental Monitoring‌: Continuously track particle count, temperature, and humidity; investigate anomalies promptly.