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The RN53 Radon Detector operates on the method of electrostatic collecting of the radon progeny Po218 and Po214. Both Po218 and Po214 decay via alpha emission. A PIN diode, which is part of the RN53 detector, continuously detects the alpha particles. An integrated energy spectrum analyzer separates the signal of undesired decay products. The rate of the output pulses of the RN53 is a direct measure for the radon gas concentration in the sampled air.

Electrostatic collecting of the decay products of the radon gas is a precise and reliable method to get a representative measure for the concentration of radon in the environment being monitored.