Air quality has traditionally been measured with Official Reference Stations which accomplish the Data Quality Objective (DQO) requirements of the Directive 2008/50/CE.
During the last years, air quality monitoring equipment has suffered rapid growth and development. Low-cost sensors designed to measure atmospheric particles and gases have been used to be integrated into different air quality monitoring devices.
We can find specific devices for indoor and outdoor applications in the market. Regarding the specific devices for outdoor applications, depending on its accuracy and uncertainty, as well as if they have a software to gather and analyse the data, we will find air quality monitoring systems designed to be complementary measurements to the reference stations, while other air quality devices are designed to be used as personal exposure devices.
The main distinctions between the different outdoor air quality monitoring devices are:
- Reference air quality stations require significant infrastructure and trained personnel to operate them. It releases very high accurate data, with an installation and operation cost from thousands to hundreds of thousands of euros. They used specific reference methods to obtain the data according to the Directive 2008/50/CE.
- Sensor-based air quality monitoring systems: air quality monitoring devices (or mini-stations) that take the data and an advanced software for the data analysis and remote management of the device. The air quality monitoring devices are smaller, much more economic (10 times less in cost), and less bulky than the reference air quality stations, but with lower accuracy. They do not want to substitute the official air quality monitoring stations, but to complement them.
- Personal exposure and portable air quality monitoring devices are designed to be portable and their price is around 100€. They have poor accuracy, but they are useful as information devices, for education purposes and to set thresholds to different health risks.