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Particle measuring device BQ21
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Particle measuring device BQ21

Bluetooth® environmental measuring device with smartphone app for recording/evaluating pollution with particulate matter due to inhalable dust (PM10) and alveolar dust (PM2.5)

Particle measurement protects employees, customers, guests and students

Excessive dust exposure at the workplace does not only endanger the health of employees and colleagues. Inventory, products that are to be processed and technical equipment also suffer from increased particle concentrations in the room air. For this reason, many countries have established statutory limit values for fine dust concentrations. Complying with these limit values must be regularly checked, especially in the workplace, but also in schools, daycare centres, care facilities and public authorities.

Inspecting the air quality made easy BQ21 with bluetooth® connectivity

With the smart bluetooth® hand-held measuring device BQ21, you can keep an eye on the particle load in the surrounding air even over longer periods of time. The particle measuring device with a flash memory for 5,000 data sets records all health-relevant room climate parameters such as air temperature, humidity level and dust fractions (< 10 micrometres) as PM10 and PM2.5 according to the internationally acknowledged PM standard (Particulate Matter, number, size and mass concentration of particles in the air). The air pollution is displayed on the 2.0 inch colour display either numerically in micrograms per cubic metre (µg/m³) of room air or as number of particles. Moreover, a colour bar indicates the current particle burden.

Acoustic alarm signal for poor air quality

Particularly convenient: The limit values for good air quality defined by the WHO (World Health Organization) are already saved in the BQ21. If the particle load or particle concentration exceeds the WHO alarm limit, an acoustic signal will be emitted.

Evaluation and documentation including MultiMeasure mobile app

As an environmental measuring device of the latest generation, the BQ21 is 100 per cent "MultiMeasure Mobile ready" and thus prepared for all requirements of professional measurement data evaluation and documentation. Via the integrated Bluetooth® interface, the recorded measurement data is easily and conveniently transferred to a smartphone or tablet, where it can be professionally evaluated or recorded with the free MultiMeasure Mobile app.

The advantageous combination of the BQ21 and professional MultiMeasure mobile evaluation software allows you at any time to quickly and reliably draw statements about the prevailing fine dust concentration in the room air. With our professional, cloud-based software MultiMeasure Professional, a wide range of analysis options is included such as the logging function for long-term measurements, graphic evaluations, the report function and data synchronisation.

Fine dust – the invisible danger

Fine dust – the invisible danger

Fine dust is one of the world's biggest environmental risks. Harmful levels of particulate matter in the outdoor air also cause indoor levels to rise.

More information regarding the fine dust issue can be found here ...

Health hazards caused by inhalable and alveolar dust

Particulate matter that is dangerous to your health is a complex combination of various particles and is divided into different fractions based on size. Dust can cause severe irritation and diseases of the respiratory tract, skin and eyes depending on the type, particle size and place of deposit.

Therefore, regular checks of the particle load in the room air is recommended in order to implement targeted solutions to reduce the particle load and to protect all present persons.

Inhalable dust (PM10) – suspended particles inhaled through mouth and nose

Dust that can be inhaled and advances right up into the nasal cavity is called inhalable dust (formerly called "coarse dust"). It defines all dust particles with an aerodynamic diameter of less than 10 µm as dust particle size PM10. This highly visible dust is mostly produced on construction sites, in the production sector or when performing craftwork and is also carried into the room when windows are open.

Alveolar dust (PM2.5) – ultra-fine alveolar suspended particles

The dust particle size PM2.5  is also known as alveolar dust and comprises ultra-fine particles with an aerodynamic diameter smaller than 3 micrometres. These ultra-fine particles are so small that they can penetrate even the smallest branches of the lungs, the alveoli (pulmonary alveoli). The best-known sources of particulate matter include emissions from combustion engines and industrial facilities, but also the abrasion of brakes and tyres on the road. This means that even modern electric cars produce harmful particulate matter.

For comparison: A human hair has a diameter of approx. 50 to 70 µm which is 5 to 7 times larger than inhalable dust and up to 28 times larger than alveolar dust.

MultiMeasure Mobile app – smart measuring data acquisition and evaluation of measuring data

With the free MultiMeasure Mobile app the captured measurement data becomes even more transparent. Just like the analysis software MultiMeasure Studio Professional 2.0 developed by Trotec for administration, analysis and report generation of measurement data on your PC, the free MultiMeasure Mobile app for Android and iOS devices also allows for professional measurement data management with a multitude of useful functions. The BQ21 hand-held measuring device and numerous other measuring devices with bluetooth® interface are automatically identified by the app and can be quickly, easily and wirelessly connected to the mobile terminal device.

The functionality of the MultiMeasure Mobile app is way beyond the simple indication of the captured measurement values. All recorded data can be displayed either numerically or in form of a chart and, by means of the logging function, can also be recorded as a series of measurements for long-term evaluation. Assigning measurement data to different projects (e.g. departments, rooms, buildings, etc.) with the app that handles a great number of clients is a child's play – including text and report templates for professional measurement data reports.

Info video on appSensors and MultiMeasure Mobile

In our video you can get a quick overview of the measurement options of the Trotec appSensors and get first insights into the functionality of the MultiMeasure mobile app. Watch it now!

Watch the video now!

Direct link to MultiMeasure Mobile in the app store:

MultiMeasure Mobile for Android
MultiMeasure Mobile for iOS

Technical details of the BQ21

BQ21 – dimensions
It's obvious: For invisible health risks in the room air, innovative solutions are needed to reliably detect and eliminate harmful pollutants. With the BQ21, this works out with incomparable ease and with the most compact dimensions. It only takes one push of a button and the quality of the room air becomes obvious.
BQ21 – with integrated foot
For permanently monitoring the air quality, the BQ21 is equipped with a practical foot to place the device clearly visible on the table or in other central positions in the room. A convenient tripod connection with screw thread is also already integrated. The air quality (PM10/PM2.5), room temperature and humidity level are clearly indicated on the display.
BQ21 – compatible with the Multi Measure Mobile app
Do not let the compact dimensions of the BQ21 mislead you. In combination with the Multi Measure Mobile app, the hand-held measuring devices shows its true size. A wide range of evaluation tools and report functions turn the smartphone or tablet into a professional measuring station with almost unlimited possibilities.
BQ21 – warning if particle load or particle concentration is exceeded
The limit values for good air quality defined by the WHO (World Health Organization) are already saved in the BQ21. If the particle load or particle concentration exceeds the WHO alarm limit, an acoustic signal will be emitted.

BQ21 – daycare centre/school
Protects children, pupils, child care workers and teaching staff from the dangers of airborne hazards. Regular ventilation with open windows opens the doors to pathogens and pollutants in the room air. With the BQ21, you create safe spaces for learning and playing. Pollution with particulate matter becomes immediately visible and can be eliminated with suitable measures.
BQ21 – nursing homes
Senior citizens and people in need of care who are disadvantaged by diseases and particularly at risk due to their age are especially protected when using the BQ21. At an early stage, the hand-held measuring device detects the smallest changes and pollution of particulate matter in the air which can become a health risk, especially for older people.
Technische Daten im Vergleich

All particle counter for air quality in direct comparison:

To find the particle counter which exactly meets your requirements, please consult the concise overview of all particle counters for air quality from Trotec, which we're providing to you here so that you can compare them directly to each other.

Models which you do not wish to include in your comparison can be easily dismissed with only one click.

Technical data by comparison

A few practical benefits:

  • Compact environmental measuring device for the detection of particulate matter pollution and climate data
  • 2'' colour display for simultaneous indication of all measured parameters
  • Memory space for up to 5,000 data sets
  • Direct conversion and display of the concentrations of inhalable and alveolar dust fractions contained in the room air stated in µg per m³ of air
  • Additional colour indicator display with automatic acoustic alarm for the quick detection of critical particle concentrations
  • Automatic switch-off function
  • Integrated tripod connection and foot

MultiMeasure Mobile – all of the app's advantages at one glance:

  • Automatic identification of the BQ21 and other measuring devices with bluetooth® interface
  • Quick and intuitive navigation
  • Numerical measured value indication or else in form of a chart / matrix
  • Integrated report function for the documentation directly on site
  • PDA function for the organization of measurement data and documents
  • Customer management already integrated
  • Manifold analysis options directly in the app
  • Storage of measured values linked to photos
  • Matrix measurements, also linked to photos
  • Complete data synchronization with MultiMeasure Professional via cloud

 standard equipment

 optionally available

 not available


Mini-Partikelmessgerät BQ21 show in Trotec online shop

Technical data

Technical data
General information
  Article number 3.510.205.095
Particle concentration
  Number of channels 2
  Channel sizes 2,5 µm, 10 µm
  Detector type Light-scattering measurement
Particle mass conversion
  Particle mass conversion 2.5 µm, 10 µm
  Min. measuring range | Particle mass conversion [µg/m³] 0
  Max. measuring range | Particle mass conversion [µg/m³] 2,000
  Resolution | Particle mass conversion [µg/m³] 1
Air temperature
  Min. measuring range | Air temperature [°C] 0
  Max. measuring range | Air temperature [°C] 50
  Min. measuring range | Air temperature [°F] 32
  Max. measuring range | Air temperature [°F] 122
  Accuracy ± 0 °C - 50 °C [°C] 1
  Accuracy ± 32 °F - 122 °F [°F] 2
  Resolution [°C] 0.1
  Resolution [°F] 0.1
Relative humidity
  Min. measuring range | Relative humidity [%] 0
  Max. measuring range | Relative humidity [%] 100
  Accuracy 0 % - 20 % [%] 5
  Accuracy 20 % - 80 % [%] 3.5
  Accuracy 80 % - 100 % [%] 5
  Display resolution [% RH] 0.1
  TFT colour LCD 2.0"
  220 x 176 px
Memory organisation
  Internal flash memory 5.000 measurements
Power supply
  Internal battery (Li-ion)
Housing design
Ambient conditions
  Operation - min. temperature [°C] 0
  Operation - max. temperature [°C] 40
  Operation – max. relative humidity (non-condensing) [%] 80
  Storage - min. temperature [°C] -10
  Storage - max. temperature [°C] 50
  Storage - max. relative humidity [%] 90
  Length (packaging excluded) [mm] 188
  Width (packaging excluded) [mm] 35
  Height (packaging excluded) [mm] 52
  (packaging excluded) [kg] 0.175
Standard scope of delivery
Standard scope of delivery
  Measuring device
  Li-ion battery (integrated)
  Wire stand
  Mini USB cable
  Charger (USB 5 V, 1 A)
  Getting started guide
Ascertainable measured values and functions
Internal sensors
  Particle concentration [n/l]
  Air temperature [°C]
  Air temperature [°F]
  Relative humidity [%]
Functions and features
  Simultaneous measurement PM2.5 and PM10
  Bar graph indicator
  Switching function °C/°F
  Memory for 5,000 measured values
  Bluetooth interface
  Automatic switch-off
  Battery status indication
  ¼ inch tripod thread
  Integrated foot

 standard equipment

 optionally available

 not available



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