Deuterium analysis in cement aerosols using CF-LIBS

The operation and decommissioning of nuclear facilities, including fusion devices and advanced fission reactors, lead to the production of tritium, which can migrate through materials and be released into the environment. During maintenance and dismantling activities, tritium can become trapped in metallic or cement dusts that can be released as aerosols, raising significant safety and environmental concerns. Measuring tritium in particles remains challenging, as conventional analytical techniques require sampling and are not suitable for real-time monitoring. Laser-Induced Breakdown Spectroscopy (LIBS) offers a promising alternative by enabling direct, in situ , and real-time quantitative chemical analysis of aerosols. However, hydrogen isotope detection by LIBS is particularly demanding due to high excitation energy requirements, small isotopic shifts, matrix interferences, and plasma non-equilibrium effects. To address these topics, this work investigates the feasibility of detecting hydrogen isotopes embedded in cement aerosols representative of decommissioning scenarios using a calibration-free LIBS approach. Deuterium is used as a non-radioactive surrogate for tritium. The cement aerosol exhibits a median aerodynamic diameter of 5 µm and a mass concentration of ( 178 ± 21 ) mg/m 3 . Under these conditions, statistical analysis indicates that a maximum of approximately 3 particles are vaporized per 100-shot acquisition. Despite this extremely low sampled mass, the deuterium signal is reliably identified and modeled, yielding a mean D/H atomic ratio of ≈ 0.26 , with values ranging from ≈ 0.14 to ≈ 0.33 across acquisitions. These results demonstrate that CF-LIBS can provide quantitative isotopic information in a regime dominated by discrete particle sampling and low signal-to-background ratios, opening perspectives for real-time monitoring of tritiated aerosols in nuclear decommissioning environments.