This monitor displays both particle count and particulate mass (PM) to give a fuller picture of your air than standard PM-only monitors. PM shows the total weight of particles, but weight alone can miss huge numbers of sub-micron particles small enough to enter the lungs and bloodstream. Particle count shows how many particles are present, even when PM looks low.

If PM2.5 appears low but particle count is high, the air may still contain millions of tiny particles that don’t register as mass. For everyday use, PM helps with compliance and general air quality, while particle count is better for spotting trends, indoor sources, and changes in real time.

The particle counter is designed for trend detection, not regulatory accuracy. Like all consumer particle counters, it has a margin of error and is sensitive to humidity and airflow. Its job is simple: reveal relative change. When you cook, ventilate, open a window, or run an air purifier, you’ll see the shifts immediately.

It’s ideal for identifying spikes in sub-micron particles when PM values remain low.

Understanding the data

• 0.3 µm – Sub-micron count; very fine aerosols (note: ultrafine particles are <0.1 µm)
• 0.5 µm – Sub-micron count; combustion particles and secondary aerosols
• 1 µm – Fine particle count; general respirable particles (typically the most stable channel)
• 2.5 µm – Aligns with PM2.5; smoke, combustion residue, urban pollution
• 5 µm – Coarse count; dust, fibres, larger debris
• 10 µm – Aligns with PM10; coarse dust, pollen, mechanical disturbance

Counts = how many particles are in each size range
PM values = estimated mass of all particles up to that size

Reading the screen (examples based on the display image)

• PM10 is higher than the 10 µm count because PM10 includes all smaller particles too.

• PM2.5 can match the 2.5 µm count because larger particles dominate the mass, even if smaller ones are far more numerous but carry little weight.

• PM1 can be low because sub-micron particles contribute very little mass despite being abundant.

We developed this monitor to address an important gap in public and institutional awareness of air quality. Most air quality monitors report only particulate mass (µg/m³), which shows the total weight of airborne particles. While this is useful for compliance, it can hide the presence of ultrafine particles (UFPs) that are extremely small, numerous, and harmful to health. Air can therefore appear clean, with low PM2.5 readings, while actually containing very high numbers of invisible fine particles.

PM values are best for regulatory comparison, while particle count reveals how many particles are present, especially in the sub-micron range. Smaller particles reach deeper into the lungs and bloodstream, so they pose a greater health risk despite their low total mass.

When interpreting particle count data, it is worth considering sensor performance. Most low cost particle counters are most accurate in the 1.0 to 5.0 µm range. The 1.0 µm channel tends to provide the most reliable trend data indoors. The 0.3 µm channel can be used as an indicator of ultrafine particle activity but should be interpreted with caution due to natural measurement limits. At the other end, readings above 10.0 µm are often less reliable because of sampling losses and should be viewed as supplementary.

By displaying both mass and particle counts, it is possible to see PM2.5 in the blue (good) range while 0.3 µm or 0.5 µm particle counts are in the dark red (severe) zone. This indicates the presence of large numbers of very small particles that contribute little to mass but carry significant health risk. In such cases, particle count provides the more relevant signal, particularly indoors, in urban environments, or during combustion events.

For health protection, filtration checks, and source identification, users should interpret particle count alongside PM mass, giving more weight to count data when submicron particles dominate. Trends in the 1.0 µm and 3.0 µm channels are especially helpful for tracking short-term changes that may not appear in mass readings.

Summary interpretation

• Blue / Green: Normal, healthy indoor air
• Amber: Early warning - rising particles or moderate pollution; indicates pollution from indoor sources, poor outdoor air, or activity changes
• Red / Dark red: Unhealthy levels - likely visible dust, odour, or haze. Strong ventilation or filtration needed

Download the guide for more information.

Download the guide for more information.

Download the product manual here.

How long does the battery last? 

Although this unit is designed for permanent wiring, it does have a battery that can last up to 5 hours. To preserve the battery life when on the move, switch the unit off and switch it on when you need it. 

How accurate are the particle counters for measuring sub-micron particles? 

This model is marketed as a consumer model, not a lab-based instrument so if you are looking for accuracy, you won’t find anything in this price range for low-cost sensors (LCS). What this will do is show you the trends and to raise awareness of the dangers that still lurk when PM2.5 is low. The accuracy improves the larger the particle count so use this as a guideline: 

• 0.3 (LCS don’t count well) 

• 0.5 (LCS can count them a bit better) 

• 1.0 (LCS can count them much better) 

• 3.0 (Most LCS can count them) 

• 5.0 (Most LCS can count them) 

• 10.0 (Most LCS cannot count them) 

This is not unique to the Airbon particle monitor, this tends to be the view for most LCS in the market 

Particle count 0.3 always seems to be high. Why? 

To be honest, there is no safe level of air pollution so the smaller the particle, the more damage it can do to our bodies. There is also no guidelines for any smaller than PM2.5 so while we can change this, there will be few scenarios where there aren’t higher levels of smaller particles.

Is there an app? 

Yes, we use the AQI.in app. Although this is largely focused on India, it will soon have more UK based data. Click on ‘Add Device’ at the bottom and follow these instructions to connect your device 

Does the unit only show real-time data? 

Yes but you can view 7 day and 30 day data on the free app. The app also comes with premium features which will be available soon.

How frequently is data refreshed? 

The data is updated every 30 seconds, this includes updates to the AQI.in app although if you already have the app open, you may need to swipe down to refresh the screen. 

Does the particle monitor store data locally, or does it require a network connection?For the particle monitor, there is no storage on the unit, it needs to be connected to WiFi. This module does not allow for storage via the SD card but future iterations can have this.

Download the troubleshoot guide here.