Use of cavity ringdown spectroscopy (CRDS) to deliver nitrate radicals for indoor surface chemistry.
Ham JE; Flemmer MM
Proceedings of Indoor Air '11, The 12th International Conference on Indoor Air Quality and Climate, June 5-10, 2011, Austin, Texas. Santa Cruz, CA: International Society of Indoor Air Quality and Climate (ISIAQ), 2011 Jun; 1:344-345
Cleaning and room deodorizing are common activities that can introduce a number of volatile organic compounds into the indoor environment. Application of these chemicals leads to diffuse gasphase "clouds" and/or adsorption to surfaces also present indoors. These compounds can then react both in the gas phase and/or on surfaces with indoor oxidants such as the nitrate radical (NO3.) resulting in the formation of new chemical species that can be emitted into the indoor environment and affect occupant exposure. In order to simulate real world concentrations (1 - 58 ppt) of nitrate radicals that are expected to be indoors as modelled by Sarwar et al. (Sarwar, 2002) and measured Nojgaard (Nojgaard, 2010), a sensitive absorption technique such as cavity ringdown spectroscopy (CRDS) may be employed. CRDS can be used to deliver accurate NO3. concentrations for gas or surfacephase experiments. Several CRDS measurements of NO3. have been made in the atmospheric environment with instruments having detection limits in the sub ppt range (Ayers, 2005, Brown, 2005). To investigate the reactions of the nitrate radical with aterpineol on a silanized glass surface, a custom CRDS system was developed. This platform will describe the instrument, show NO3. calibration curves from this system, and discuss the preliminary results from aterpineol/ NO3./silanized glass reactions.
Cleaning-compounds; Deodorizers; Organic-compounds; Volatiles; Indoor-environmental-quality; Indoor-air-pollution; Exposure-levels; Risk-factors; Gases; Nitrates; Environmental-exposure; Environmental-hazards;
Author Keywords: cavity ringdown spectroscopy; nitrate radicals; aterpineol; indoor surface chemistry
Proceedings of Indoor Air '11, The 12th International Conference on Indoor Air Quality and Climate, June 5-10, 2011, Austin, Texas