AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Portable Near-real Time Spectrometer for Measurement of Elemental Concentration of Aerosols
PRAMOD KULKARNI, Lina Zheng, G.J. Deye, M. Eileen Birch, Centers for Disease Control and Prevention, NIOSH
Abstract Number: 553 Working Group: Instrumentation and Methods
Abstract Compact, field-portable sensors that can provide real-time information about chemical and physical properties of aerosols are valuable tools for exposure measurement. Real-time instruments are an important driver for the future of exposure sciences. An Aerosol Spark Emission Spectrometer (ASES) has been developed for near real-time measurement of elemental concentration of aerosols in the personal breathing zone. The instrument employs atomic emission spectroscopy using spark microplasma as the excitation source. Particles are collected on the tip of the electrode and then subject to ablation and excitation by the microplasma, which leads to significant improvement in measurement precision, limits of detection, and time resolution of measurement. The compact instrument can simultaneously measure most elements in the periodic table at a time resolution of few seconds to few minutes. Algorithms were developed for real-time spectral analysis to obtain quantitative elemental information as well as qualitative insights via chemometric techniques. The instrument was calibrated for various elements, including carbon, and their detection limits were determined and were found to be in the range of few tens to hundreds ng/m^3. Its performance was evaluated using parallel samples collected using filters and analyzed using mass spectrometry. Field measurements were conducted to characterize aerosols in the breathing zone of a mobile person and compared with those from the filter samples. We will present the overall design and development of the instrument, as well as results from the laboratory and field studies designed to evaluate analytical figures of merit of this new instrument.