Citizen-science sensor
During the project, measurements will be made with two instruments:
1. Sensor measuring particulate concentration (PM 2.5, PM 10) to be used continuously by citizens.
The parts of the device, can be purchased in one piece from several places, including China, Poland on this site, and most parts can be found in various electronics stores.
A Hungarian company sells the device assembled, and they have also added a little to the basic design: they have put a grid on both ends of the protective tube to prevent insects from moving in. The company's webshop is available here, sometimes orders are fulfilled immediately, sometimes within a few weeks, and the current price is 25.000 HUF.
You can find more information about the sensors (instructions on how to install them) here
If you have ordered parts from a distant country or assembled them yourself from various electronics shops, we have made a video for you on how to assemble them.
If you bought it pre-assembled from a Hungarian manufacturer, you just need to plug it in, configure it, register, and enjoy the data showing the air quality around you.
Air quality measuring walk
We measured the air quality in the centre of Budapest from Heroes' Square to Vigadó Square with three portable air quality measuring devices, which measure the particulate matter (aerosol) content of the air at indicative levels. Our tools are the Atmotube Pro, which measures PM1, PM2.5 and PM10 (under 1, 2.5 and 10 micrometers size), a mobile version of a device that is easily available to the public and is being increasingly used in Germany and already in many other countries by Sensor.community, which also measures PM2.5 and PM10 in the air, and a Testo Discmini ultrafine particle counter measuring particles from 10 to 700 nanometers size.
About the installable and convertible (to mobile) sensor of the Sensor.community you can read more here, and information on how to purchase and install it is also available. It can be made mobile simply by using a powerbank and connecting to the phone's hotspot.
Measuring point 1 - Heroes' Square: At the first station, the ultrafine particle counter measured between 20,000 and 24,000, which is normal for a busy urban road, but could have been lower due to the large space, moving air and moderate car traffic. However, it is important to note that PM10 levels were high at this point, presumably due to air pollution from heating.
Measuring point 2 - Bajza utca underground stop: At this stop we were closer to the car traffic, there was congestion and continuous car traffic in our immediate vicinity, which is reflected in the data measured at this point. The graph of ultrafine particles shows a very high value, probably a diesel vehicle passed us. Our simpler sensors do not show much change from the first station.
Measuring point 3 - Kodály körönd: At the next three stations (up to Oktogon) the ultrafine particle counter showed sometimes extremely high values, this was due to the increased car traffic. The PM10 and PM2.5 values at these three stations also showed the usual but decreasing trend along the busy roads in the city centre, with decreasing impact of solid combustion, while traffic pollution became more prevalent towards the city centre.
Measuring point 4 - House of Terror/Vörösmarty street underground station:
Measuring point 5 - Oktogon: PM10 and PM2.5 values are relatively low, with an average number of ultrafine particles of around 30,000-40,000, which clearly indicates the dominance of traffic-based air pollution.
Measuring point 6 - Liszt Ferenc square: construction works were taking place next to the square, but this did not have a noticeable effect on the results measured here, probably the construction distortion was in a larger range than the sensitivity of the sensors.
Measuring point 7 - Opera: As the peak hours passed, traffic slowed down, and as we approached Bajcsy-Zsilinszky road and the Danube, the ultrafine particle number values decreased somewhat. A slight increase in air movement contributed to this. PM10 values are slightly higher than expected, possibly due to nearby street vendors, shop heat emitters, Christmas fair preparations, burning activities.
Measuring point 8 - Bajcsy-Zsilinszky road underground stop: The number of ultrafine particles was typical for the traffic junction.
Measuring point 9 – Erzsébet square: the data measured next to the official monitoring station are high, especially for ultrafine particles, as we were close to the cars.
Here the values measured by the official station are much higher than our PM2.5 and PM10 values over the same period, this difference can be due to the fact that our measurements are a few minutes, while the station only gives hourly averages, we probably caught a more ventilated 5 minutes in our own measurement, and the sensitivity of the official station is of course better than the equipment we use, it can detect more pollutants.
Measurement point 10 - Vigadó square: high values were measured at the last station, which is located next to the Danube. Here, the air movement was much higher, and we could still see the increased concentration of particulate matter. This is likely to be due to the charcoal-grilled food from the nearby Christmas fair vendors. As there was a lot of construction work going on near the Vigadó, it is possible that this was also detectable in the measurement at the measuring point. In a similar measurement study, it is worth looking for the source. The easiest way to do this is to start in one direction and head in the direction of increasing air pollution until we reach the highest pollution level.
