[en] In this paper a dosimeter is proposed for the purpose of detecting noble gas releases (principally Xe-133) from nuclear power plants. The dosimeter consists of two Li₂B₄O₇:Cu (LiBO) elements and one CaSO₄:Tm (CaSO) element. One LiBO element is enclosed only in plastic and is used to determine shallow dose, while the LiBO and CaSO pair, which are used to determine deep dose, are enclosed in a 1070 mg/cm² aluminum sphere and plastic. The dosimeter is designed to overcome the three major problems involved in monitoring for Xe-133: the effect of angular response, differences in irradiation geometry (overhead plume vs. submersion), and interference from naturally occurring high-energy gamma rays. Laboratory test data are presented to demonstrate the proposed dosimeter's response characteristics