still for bestemning of a metverde representing content radondottrar in air in a room and device for anvendning dervid

摘要

-particles from the decomposition of radon daughters RaB and RaC are detected from at least an essentially confined, free room air volume via the calculation of detector pulses during a set period of time. Detection is carried out at such a distance from surfaces in the room, whereupon the radon daughters can be deposited so radiation from the decomposition of deposited radon daughters are essentially undetected. During detection, the deposit of radon daughter at the opening to the detector is prevented; especially on the window of the detector by having a radium-absorbent and radium disposing cover go past the opening. A measurement test value is calculated based on an activity-representative pulse count N, obtained through calculation. In particular, a measurement test value EEC' = k1 N(RaB) + k2 N(RaC) + k3 where k1, k2 and k3 are determined via calibration at known radon daughter contents during the utilisation of linear multiple regression.IMAGE