Do Air Purifiers Remove Dust?

Quick Answer: Yes – air purifiers can be very effective at removing airborne dust particles. However their effectiveness depends on a range of factors including room size, amount of dust and ACH (air changes per hour) rating of the air purifier

How Air Purifiers Remove Dust

Air purifiers use a mechanical filter, most commonly a HEPA filters to capture airborne particles down to 0.3 microns – in more familiar terms 0.0003 millimetres. To give you an idea of how efficient these HEPA filters are – a human hair is around 70 microns thick.

An internal fan is used to draw air into the air purifier which is then passed through a filter made up of extremely fine strands of plastic or fibreglass woven together to form a net like structure.

Airborne particles, including dust, that are larger than 0.3 microns are trapped in the filter with the purified air then released back into the room.

With household dust particles ranging between 0.5 and 100 microns, any true HEPA air purifier will efficiently capture and remove dust from your home.

It’s important to note that the ability for your air purifier to remove dust and other particles from the air relies on regular replacement of the HEPA filter as it can lose its efficiency over time with regular use.

What is Dust?

This is where it gets pretty disgusting… According to scientists at the University of Arizona, dust can be made up of a variety of localised environmental particles but mostly commonly consists of shed bits of human skin, decaying insects, animal fur, lint, fabric fibres, soil, particulate matter from cooking and smoking and even lead, arsenic and DDT! 

Other common components of dust can include pollen, mould spores and bacteria from dust mite droppings. 

air purifier removing dust

The Dangers of Dust To Your Health

Obviously no Australian would like the thought of inhaling dead skin, insects and dirt – however beyond the yuck factor, breathing in dust can be detrimental to your health.

The human lungs contain tiny hairs called ‘alveoli’ to trap foreign bodies and stop them from entering. Generally, the alveoli can filter particles down to 1 micron however particles larger than this can still cause severe respiratory system issues, particularly in those who have Asthma.

These larger dust particles are known as inhalable dust.

Respirable dust, which is smaller than 10 microns (extremely small) can be breathed deep into your lungs and lead to potential lung damage including Pneumoconiosis, Chronic Obstructive Pulmonary Disease (COPD), Asthma, Fibrosing alveolitis & Cancer.


dust particle size
Dust particle sizes compare to 5 cent piece - credit WorkSafe QLD

Tips for Maximising the Effectiveness of an Air Purifier for Removing Dust:

  1. Consider Room Size & Air Changes Per Hour (ACH): To ensure your air purifier operates at its peak efficiency, match it with the size of the room. Also, pay attention to the number of air changes per hour (ACH) the purifier offers. A higher ACH means the purifier can clean the entire volume of the room more frequently.
  2. Proper Placement: The location of your air purifier can greatly affect its efficiency. For best results, place the purifier in a central location, away from walls or large pieces of furniture which may restrict airflow. If you’re specifically concerned about dust, a location with higher foot traffic could be a good spot, as movement tends to stir up dust particles.
  3. Utilize Pre-filters: Many air purifiers come equipped with a pre-filter. This is designed to catch larger particles, such as hair and larger dust particles, which in turn can help prolong the life and efficiency of the primary filter.
  4. Regular Maintenance: In addition to replacing the primary filter as recommended by the manufacturer, you should regularly inspect and clean the external surfaces of the purifier. Ensuring that the unit is free from dust or grime can aid in its performance. If your unit has a pre-filter, clean or replace it regularly.
  5. Limit External Sources of Dust: While your air purifier works hard to remove dust, you can assist by limiting the sources. Regular cleaning routines, including vacuuming and dusting, can reduce the amount of dust in your environment. Using door mats, removing shoes at the entrance, and keeping windows closed on windy days can also minimize dust intake.
  6. Monitor Noise Levels for Comfort: Although this doesn’t directly enhance dust removal, the noise level can impact overall user satisfaction. If your purifier is too noisy, you might be inclined to turn it off or reduce its power. Choosing a unit that is quiet yet efficient ensures it can run continuously without causing disturbance, ensuring maximum dust removal.