How to Read ISO 16890 Filter Labels Without the Jargon

If you’ve ever looked at an air filter label and thought it was written in another language, you’re not alone. ISO 16890 can seem technical at first, but once you know what the labels mean, it becomes much easier to choose a filter that suits the job.

In simple terms, the rating tells you what size particles the filter is designed to capture more effectively. That matters whether you’re looking after a home, a shop, an office, a school, or a larger commercial HVAC system.

What ISO 16890 is actually telling you

ISO 16890 is a performance standard used to describe how well an air filter captures different sizes of airborne particles. Instead of relying on older-style class names, the label focuses on particle size ranges that are easier to relate to real ventilation and air conditioning systems.

The key part of the label is the ePM rating. That stands for the efficiency of the filter against particulate matter within a specific size range.

You’ll commonly see labels such as:

• •ePM1
• •ePM2.5
• •ePM10

The number tells you the particle size range the rating relates to. Smaller numbers mean smaller particles.

In everyday terms:

• •ePM1 targets finer particles
• •ePM2.5 targets very small particles, but not as fine as ePM1
• •ePM10 targets larger airborne particles such as coarse dust and pollen-sized material

That does not mean a filter only works on one size. It means the label highlights where the filter’s performance is measured.

What ePM1, ePM2.5 and ePM10 mean in plain English

ePM1

An ePM1 filter is aimed at finer particles. These are the kinds of particles that can stay airborne for longer and may be found in indoor spaces with higher filtration needs, such as offices, healthcare-adjacent areas, laboratories, clean process areas, or buildings with sensitive equipment.

For HVAC systems, ePM1 is often chosen when the goal is to control finer dust and maintain cleaner supply air through the system.

ePM2.5

An ePM2.5 filter captures a middle range of particle sizes. It is often a practical step up from coarse filtration where a site needs better particle capture without moving to the most demanding fine-particle application.

This can suit:

• •Offices and meeting spaces
• •Schools and education facilities
• •Retail spaces
• •Apartment common areas
• •General commercial HVAC systems

If you are trying to balance particle capture with airflow and system design, ePM2.5 is often a useful middle ground.

ePM10

An ePM10 filter focuses on larger airborne particles. That can include coarse dust, lint, and other bigger debris that often loads a filter faster in dusty environments.

This rating is commonly relevant where the main aim is to protect equipment, reduce heavy dust loading, or provide initial filtration before a finer final filter.

Good examples include:

• •Workshops
• •Warehouses
• •Plant rooms
• •Sites close to roads or construction
• •Systems with a pre-filter stage

How to match the rating to the application

The right ISO 16890 rating depends on what the system is trying to do, not just how “fine” the rating sounds.

A practical way to think about it is:

• •If the site sees a lot of coarse dust, an ePM10 stage may be a sensible starting point
• •If the building needs better general indoor air filtration, ePM2.5 is often worth considering
• •If the system has higher filtration demands, ePM1 may be appropriate as part of a staged arrangement

For many HVAC systems, filtration is not just one filter in one location. It can be a combination of pre-filtration and finer final filtration, depending on the fan, housing, airflow requirements, and the space being served.

Homeowners

In homes, ISO 16890 labels matter when you want to understand what the filter is doing inside a ducted system, air handler, or return-air setup.

If the main issue is dust build-up in the system, a coarser filter stage may be suitable. If the home has a more demanding indoor environment, or the system design allows for finer filtration, the label helps you compare options more clearly.

If you’re unsure, check the equipment instructions and speak with the installer or mechanical services engineer. The wrong filter choice can restrict airflow or underperform for the application.

Facility managers

For facility managers, the label helps you choose filters based on the building’s actual operating conditions.

Think about:

• •Occupancy patterns
• •Outdoor dust exposure
• •Nearby traffic or construction
• •Whether the system has pre-filtration and final filtration stages
• •Access for inspection and filter servicing

If the site is governed by ventilation requirements, confirm the setup against AS 1668.2:2024 with the mechanical services engineer or building owner.

Mechanical contractors

For contractors, ISO 16890 is useful because it gives a clearer view of what a filter is designed to do without relying on vague descriptions.

When specifying or replacing filters, check:

• •The filter housing dimensions and sealing arrangement
• •The airflow and pressure drop requirements of the system
• •Whether the application needs pre-filtration, final filtration, or both
• •The site’s maintenance access and inspection approach

If the application calls for a custom size or unusual frame type, it may be better to use custom air filters rather than forcing a near-match into the housing.

Reading the label without getting caught up in the jargon

A typical label may include more than one ePM result. That can look confusing, but the logic is simple: the filter may have different performance figures for different particle size ranges.

When reading the label, focus on these questions:

• •What particle size range is listed?
• •Is the filter being used as a pre-filter or final filter?
• •Does the system require a certain filtration level for the site?
• •Will the filter still allow the system to run as designed?

If you are comparing products, avoid treating the rating as the only factor. Frame design, fit, seal quality, media construction, and system compatibility all matter.

Some filters are designed to be washable - check the product instructions. Do not assume that because a filter can be cleaned, it will suit every HVAC application.

ISO 16890, older ratings and why they are not direct matches

You may still see older EN 779 class names such as G3, G4, F5, F6, F7, F8 and F9 in parts of the market. These are still widely used in Australia, even though ISO 16890 has superseded EN 779 in many contexts.

It is important not to assume a direct one-to-one conversion between old and new ratings. MERV, EN 779 and ISO 16890 describe performance in different ways, so they do not convert neatly.

If a supplier gives you an old class name and you need an ISO 16890 option, the safest approach is to look at the actual application, the filter dimensions, and the manufacturer data rather than relying on a shortcut.

When to inspect and replace filters

There is no single replacement timetable that suits every system. Inspection frequency depends on the system, site conditions and dust load.

A practical maintenance approach is to:

• •Check filters in line with the equipment or filter manufacturer instructions
• •Monitor pressure drop where gauges are fitted
• •Inspect more often in dusty sites, high-use buildings, or environments with heavy outdoor loading
• •Replace filters when they are no longer performing as intended for the system

If a site has recurring dust issues, it may be worth reviewing the filtration stage rather than just changing filters more often.

Getting the right filter for the job

The label is only useful if it matches the real-world application. A filter that is too coarse may not give the level of particle capture the system needs. A filter that is too restrictive may affect airflow or create servicing issues.

For the best result, have these details ready before you order:

• •Filter size and depth
• •Frame type and seal style
• •Equipment model or housing details
• •Whether the system uses pre-filters and final filters
• •The site conditions and dust exposure

If you need help working through the options, Total Air Filtration is a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, established in 2009. We can help supply or make the right filters for the application, including standard and custom sizes.

Call 07 3800 3448 or request a quote. You can also explore our products, arrange filter servicing, or get in touch via contact us.