ISO 16890 Explained

ISO 16890 is an international standard used to classify air filters for general ventilation systems based on their ability to remove particulate matter from the air.

Unlike earlier standards that relied on synthetic test dust, ISO 16890 evaluates filter performance using particle size fractions that reflect real-world air pollution.

Developed by the International Organization for Standardization, ISO 16890 provides a more transparent and application-oriented method for comparing air filters used in HVAC and ventilation systems.

This page explains what ISO 16890 is, how it works, and how it should be applied when selecting air filters for different environments.

What Is ISO 16890?

ISO 16890 is a global standard that defines how air filters for general ventilation are tested and classified. The standard focuses on how effectively a filter removes particulate matter of different sizes from the air, rather than relying on overall dust arrestance values.

The goal of ISO 16890 is to align air filter classification with actual ambient air conditions, making filter performance easier to understand and compare across regions and applications.

Why Did ISO 16890 Replace EN 779?

EN 779 was the former European standard for classifying air filters in general ventilation. While widely used, EN 779 relied on average dust arrestance and efficiency values that did not clearly reflect real environmental particle behavior.

ISO 16890 replaced EN 779 to address several limitations:

EN 779 used synthetic dust that did not represent ambient air pollution
Efficiency values were not directly linked to particle size
Results were difficult to compare across different environments

By focusing on particle size fractions relevant to human health and environmental exposure, ISO 16890 provides more meaningful performance data.

How Does ISO 16890 Classify Air Filters?

ISO 16890 classifies air filters based on their efficiency in removing particles within specific size ranges. Instead of a single efficiency number, the standard evaluates performance across defined particulate matter fractions.

Filters are tested and assigned efficiency values for particles in the following size categories:

ePM1 (particles ≤ 1 μm)
ePM2.5 (particles ≤ 2.5 μm)
ePM10 (particles ≤ 10 μm)

These fractions correspond to widely recognized air quality metrics used in environmental monitoring.

EN779 to ISO 16890 Conversion Table

EN 779 Filter Class	Approximate ISO 16890 Equivalent

G3 – G4

ISO Coarse

M5 – M6

ISO ePM10

F7 – F8

ISO ePM2.5

ISO ePM1

ISO 16890 Efficiency Groups Explained

Under ISO 16890, air filters are classified into efficiency groups based on their minimum efficiency value for each particle size fraction.

Common classifications include:

ISO ePM1 filters, designed to capture fine particles such as combustion aerosols and smoke
ISO ePM2.5 filters, effective against urban dust and fine particulate matter
ISO ePM10 filters, primarily used for coarse particle removal

Filters that do not meet minimum efficiency thresholds for these groups may be classified as ISO Coarse, indicating suitability for capturing larger particles only.

Common ISO 16890 Filter Examples

ISO ePM1 70%
ISO ePM2.5 65%
ISO ePM10 80%
ISO Coarse 70%

ISO 16890 in HVAC Applications

ISO 16890 air filters are widely used in:

HVAC systems in commercial buildings
Industrial ventilation systems
Healthcare facilities
Manufacturing plants

Automotive paint booths

Overview of the ISO 16890 Testing Method

ISO 16890 testing measures particle removal efficiency across the full size range of interest using particle counters.

Filters are conditioned and tested to reflect realistic operating conditions.

Key aspects of the testing process include:

Measurement of initial and discharged efficiency
Evaluation across defined particle size ranges
Determination of minimum efficiency values

This approach ensures that filter classification reflects performance over time rather than at a single test point.

How to Use ISO 16890 in Air Filter Selection

ISO 16890 helps engineers and facility managers select air filters based on actual air quality requirements rather than legacy classification systems.

When using ISO 16890 for filter selection, key considerations include:

Target particle size based on application needs
Outdoor air quality and pollution levels
System airflow and pressure drop constraints
Maintenance and filter replacement strategy

Using ISO 16890 allows for more informed decisions that balance air quality, energy consumption, and operational performance.

ISO 16890 Compared with Other Air Filtration Standards

ISO 16890 applies specifically to air filters used in general ventilation systems. It does not replace standards used for high-efficiency or cleanroom filtration.

For comparison:

ISO 16890 applies to general HVAC and ventilation filters
EN 1822 applies to HEPA and ULPA filters
ASHRAE standards are commonly used in North America

Understanding how ISO 16890 fits within the broader standards landscape helps ensure correct filter selection for each application.

ISO 16890 represents a significant advancement in how air filters for general ventilation are classified and understood.

By focusing on particle size–based efficiency and real-world air conditions, the standard provides clearer and more meaningful performance information.

For HVAC designers, engineers, and facility operators, ISO 16890 offers a reliable framework for selecting air filters that meet both air quality objectives and operational requirements.