Particulate matter observations using HM-3301 low-cost sensor

<p>The low-cost sensor was installed on September 17, 2019, and data has been taken until November 12, 2019, with some days of inactivity. During this period, the sensor has been located in both indoor and outdoor environments. In total, three different periods can be identified. The first period was from September 17 to October 14 where the sensor was installed in an indoor environment (an office at Universitat Jaume I, Castell&oacute;, Spain); the second period was from October 15 to October 30 in an outdoor environment (Vila-real, , Castell&oacute;, Spain); and finally, third period from October 31 to November 12 in an indoor environment (an office at Universitat Jaume I, Castell&oacute;, Spain). In total 3,677 observations were collected during these three periods with a rate of 15 minutes. Each observation contains a timestamp and PM1, PM2.5 and PM10 values.&nbsp;</p>