Application of laser induced plasma spectroscopy for air pollution monitoring

Laser induced plasma spectroscopy (LIPS, also LIBS) is a promising technique for the challenging issues associated with the real-time and in-situ monitoring the major elements of aerosol particulate matters. A prototype of Aero-LIPS had been set up with the techniques of aerosol beam focusing, enhanced plasma emission collector and conditional data filter to demonstrate the potential application of air pollution composition monitoring. The prototype can identify more than 40 elements from aerosols and continuously monitor 20 elements with the time resolution of 10 minutes. In the field test of an Asian dust event, the major elements, such as Ca, Mg, Al, Si, Cl, P, S, etc. have been real-time monitored, which took 77.9% part of the total particulate matter mass. The evolutions of temporal elemental concentrations went well along with the particle matter concentration. It is interesting that several persist lines of U and Th have been detected from Asian dust aerosol while their concentration in local air should range in the level of nano-grams per cubic-meter. It might indicate that the enhanced-LIPS has a potential to monitor the nuclear facility emission for Nuclear Security and Safeguards.