We describe a spectrometer-dosimeter for simultaneous and independent measu
rements of the spectral and dose characteristics of alpha-, beta-, and gamm
a-radiations. The particle-identification method used in the spectrometers-
dosimeters is based on simultaneous measurement of the particle energy E an
d its specific loss Delta E with semiconductor detectors. The dependences D
elta E(E), preliminarily computed for each sort of particles, are stored in
programmable read-only memories. Comparison of the expected and measured v
alues of Delta E for the measured energy E completely defines the type of a
particle. The method makes possible the determination of the spectral and
dose characteristics of different types of radiation, as well as the radion
uclide type and its concentration in the analyzed substance. It is shown th
at instruments based on this principle provide environmental radiation moni
toring, including monitoring of radon, thoron, and their products.