The 1-hour and 24-hour means are from the SDS011 sensor for the period ending at 00:00 16/05/24. The graph shows how the concentration of PM2.5 has varied during the 24 hours ending at 00:00 16/05/24.
A PM2.5 concentration of 0 μg/m3 corresponds to a relative risk of mortality of 1, according to the latest UK expert advice.
The same plots are available showing all Luftdaten sensors in Gloucestershire: here.
Pollution is measured for one minute every five minutes by three particle sensors: SDS011, PMS5003, and PMS7003. The sensors are mounted on a fence about 1.5m above the ground in Kingsway, Gloucestershire.
Several alternative plots are available:
The readings are sent to the plumeplotter.com server (this page), and the SDS011 reading is also sent to hackair.eu and luftdaten.info to display on their maps.