Monitoring and measurement of radon activity in a new design of radon calibration chamber

A new radon calibration chamber has been designed, constructed and tested to set various desired environmental parameters. The chamber is cubic with two trapezoid sides with a total volume size of 0.498 m3.The three parameters, temperature, humidity and flow are controlled in the range of 20–45 °C (±2 °C), 10–70% (±2.5%) and 0.2–10 m3/min (±0.1 m3/min) respectively. The chamber is equipped with a controllable speed centrifugal fan to achieve a desirably uniform radon flow rate. Many parts of this system are controlled and monitored with a PLC (Programmable Logic Control) and HMI (Human Monitoring Interface) software (Citect Scada). Finally a radon detector (Alpha-Guard) registers the activity parameter.