The real time air quality monitoring network is complemented by a passive diffusive tube network. The Environment and Resources Authority (ERA) has deployed 98 NO2 tubes and 90 VOC tubes throughout Malta and Gozo. The tubes are exposed for a period of 4 weeks (for a total of 13 exposure periods in one year) after which they are sent to a laboratory for analysis. The annual averages can then be interpolated to provide pollution maps as follows:
NO2 levels in Malta 2014
NO2 levels in Malta 2015
NO2 levels in Malta 2016
NO2 levels in Malta 2017
Benzene levels in Malta 2014
Benzene levels in Malta 2015
Benzene levels in Malta 2016
Benzene levels in Malta 2017