What are particle sensors?
Particle sensors are small air monitors that measure airborne particles smaller than 10 micrometers or 2.5 micrometers. These low-cost sensors are also well-known as optical particle counters; optical sensors; particulate matter sensors; air quality or air pollution sensors. Due to their simplicity and low cost, it becomes a popular way to monitor air quality.
How do particle sensors work?
Sensors use a ‘light-scattering technique to determine the concentration of particles in the air. A beam of light inside the sensor is passed through a sample of air, and particles in the sample scatter the light beam. The scattered light is measured and used to analyze the concentration of particles in the air sample. All particle sensors use similar technology but can calculate particle concentrations in different ways. They look different and vary in size.
What are the limitations of particle sensors?
- There are some limitations of particle sensors like
- Inconsistent measurement of particles from different sources.
- Particles scatter light beams differently, depending on the type along with a mixture of particles. For example, a sensor will detect particles from vehicles in a different way than particles from smoke.
- Air ventilation of enclosures and wind speed may affect the air flow inside the sensor.
- If we put a particle sensor in a box or near a wall, it may show a lower concentration of particles than if we put it in an open space. This also means if a sensor is moving, for example, if we take it on our vehicle, it will respond differently to when it’s stationary.
What are sensors used for?
- There are many useful applications for particle sensors like,
- To supplement existing air monitoring networks by increasing the geographical coverage of a network or to help identify localized air pollution problems.
- To increase people’s understanding of air quality and air pollution.
- Personal exposure monitoring, especially for people who are more sensitive to air pollution.