A laser complex for continuous real-time detection of iodine-129 isotope and nitrogen oxides (NO and NO2) is developed. The principle of operation of this complex employs such highly sensitive methods of laser spectroscopy as fluorescence and absorption techniques. The developed complex is based on He-Ne (0.63 mu m) and He-Cd (0.44 mu m) lasers. The complex can be used for measuring concentrations of iodine-129 and nitrogen oxides in the working medium in reprocessing waste nuclear fuel on radiochemical plants, which makes it possible to influence the technological process and, in particular, to improve its ecological safety. In addition, the developed complex opens up new possibilities for ecological monitoring of atmospheric air.

A laser-induced fluorescence detector for on-line control of the long-lived iodine-129 isotope concentration on the basis of a He-3-Ne-20 laser is developed. Iodine fluorescence spectra are measured, and factors determining the sensitivity of I-129(2) detection are investigated. It is shown that the detector is applicable for ecological monitoring of iodine-129 in atmospheric air, down to the level of maximal permissible concentrations of about 10(9) molecules per cubic centimeter.