ការព្យាករណ៍គុណភាពខ្យល់
ទិន្នន័យគុណភាពខ្យល់ផ្តល់ដោយ៖ the Air Quality in Wales (airquality.gov.wales)
Note that the measurement for O3 (ozone) are taken from the station: UK:Wales/Newport M4 Junction 25 and the measurement for SO2 (sulfur dioxide) are taken from the station: Caerphilly White Street