Passive method for the determination of the equilibrium factor between 222Rn gas and its short period progeny

This work describes a method which was developed to determine the concentration of 222Rn gas and the equilibrium factor F between the concentration of the gas and its progeny by means of a single device that uses two Makrofol passive track detectors. The device is completely passive and time integrated. Conditions make it very appropriate to be used in any atmospheres in which human activity takes place, such as houses, schools, works and underground mines. A series of measurements of 222Rn gas concentration and equilibrium factor F were made in different cities of the Argentine Republic and the corresponding levels of doses were estimated.