Back in April, I and uRADMonitor shipped 5 Smoggie-PM to 5 volunteers in order to help them raise awareness but also to investigate what people breathe in other parts of the world, like in Belgium, Uganda, Azerbaijan, the USA, and Spain. Unfortunately, the US volunteer doesn’t respond to my emails and he hasn’t set the monitor up yet. I hope he is fine and covid-19 or any other possible problem hasn’t affected him.
In this article, I will analyze the data from two of the locations in order to determine the Air Quality (AQ) and get some conclusions that will help my volunteers. Here are some of the photos the volunteers have sent me.
It is always recommended to place the AQ monitors under the shade as sunlight can increase the internal temperature and consequentially the measurements of temperature and humidity will be incorrect.
Spain – Murcia
The AQ monitor in Murcia is online since May 2021 so we have collected 4 months of data. According to the data PM2.5 always spike in the morning when illegal agricultural fires are lit. Saturdays are the worst days to open a window or to exercise outdoors. The maximum PM2.5 concentration was 68 μg/m3 and with an average value of 5.7 μg/m3. I compared the official data from the AQ Station (ES1633A), which is 4km far away from his house, against the Smoggie-PM and the results are very good. A Pearson’s correlation gives us a value of 0.613 (2902 data entries = 4 months) which means if we consider the distance and price point of the devices the result is very good (no corrections were applied). When we make a visual comparison of the graphs between the two monitors we noticed that the trend lines are the same but the Smoggie-PM underestimates the mass concentration. Again there is a significant distance between the two monitors. Finally, according to the ES1633A AQ station, the average PM2.5 is 12.2 μg/m3. I would suggest multiplying by two the output values of the monitor.
Baku – Azerbaijan
The AQ monitor in Baku is up and running since May as well. As we can see from the graphs Mondays, Tuesdays, Saturdays, Sundays are the worst days of the week to do outdoor activities or simply open the window for ventilation. I don’t know if there was any wildfire in the area during August, I would ask the volunteer to comment below if he knows something. After six o’clock in the afternoon, concentrations tend to rise. The maximum value that was registered was 825 μg/m3 with a mean value of 8.6 μg/m3, which is above the recommended PM2.5 values WHO has set in the 2021 Air Quality Guidelines.
Low-cost monitors offer valuable information to people all over the world. The data set they export is much denser and in real-time (much easier to access as well). Official AQ stations are accurate but slow and really expensive which means in most cases there is only one in a city that doesn’t reflect the exposure to air pollution equality across the population.