F9

F9 filters are commonly specified in ventilation systems serving environments with strict indoor air quality requirements. They provide advanced filtration performance while remaining compatible with large-volume HVAC systems.

As the upper limit of EN 779, F9 filters are often used where designers aim to approach cleanroom-level air quality using conventional ventilation technologies.

Typical Applications

F9 air filters are applied in environments where air cleanliness is critical, but HEPA filtration is not required or practical.

Common applications include:

• High-end commercial buildings

• Facilities with strict indoor air quality specifications

• Clean support areas upstream of cleanrooms

• Healthcare and pharmaceutical support zones

• Pre-filtration for HEPA-filtered systems

In these applications, F9 filters help achieve very low airborne particle concentrations within general ventilation systems.

Performance Highlights

F9 filters are engineered to deliver the highest level of filtration performance achievable under EN 779.

Key performance characteristics include:

• Maximum fine particle removal within general ventilation

• High dust-holding capacity for extended service life

• Stable airflow performance in engineered HVAC systems

• Effective protection for downstream HEPA filters

• Suitable for continuous operation in demanding environments

These characteristics make F9 filters the preferred choice when system performance and air cleanliness requirements are at their highest within the EN 779 framework.

FAQ

Is F9 the highest efficiency level in the EN 779 standard?

Yes. F9 is the highest filtration class defined under EN 779 for general ventilation filters.

Should F9 filters be replaced by HEPA filters?

F9 filters are used in general ventilation systems. HEPA filters fall under EN 1822 and are applied in cleanroom environments where higher efficiency and leak testing are required.

Can F9 filters be used as pre-filters for HEPA systems?

Yes. F9 filters are commonly used upstream of HEPA filters to reduce particle load and extend HEPA service life.

Do F9 filters require special system design considerations?

Yes. Due to their higher resistance compared to lower F-class filters, airflow capacity and pressure drop must be considered during system design and filter selection.