Measurements of Particle Deposition Rates Inside Southern California Museums
Abstract
Rates of deposition of submicrometer particles were measured inside five Southern California museums using an automated particle-counting technique on a scanning electron microscope equipped with an energy-dispersive X-ray detector combined with bulk chemical analysis. Deposition velocities to vertical and upward-facing horizontal surfaces were determined as a function of particle size for each site by analysis of indoor suspended particles sampled onto filters and particles deposited on vertically and horizontally oriented deposition plates. Measured deposition velocities to vertical indoor surfaces were in the range of 10^(−6) to 10^(−5) m/s at all sites but varied from site to site in terms of their dependence upon particle size. Deposition velocities to horizontal surfaces were in the range of 10^(−6) to 10^(−3) m/s and showed the expected increase with particle size due to gravitational settling. The deposition velocities measured by single-particle analysis are compared to deposition velocities determined by bulk chemical analysis of deposition plates and indoor ambient filter samples for several chemical species. Advantages and drawbacks of the automated particle counting technique are discussed.
Additional Information
© 1990 Elsevier Science Publishing Co. Received April 10, 1989; accepted November 20, 1989. Ambient sample collection was conducted by Lynn Salmon and Michael Jones Analysis of many of the SEM samples was performed by Nora Lowe, and IC, AA, and ammonium analyses were performed by Lynn Salmon The authors are grateful to Steven Hayward and Gustavo Delgado for their helpful consultations and assistance with the electron microscopy, and to Pat Koen for carbon-coating the samples and for helpful discussions. The cooperation and help of the staff of the five museums is gratefully acknowledged. This work was supported by a contract from the Getty Conservation Institute, Marina Del Rey, CA.Additional details
- Eprint ID
- 69113
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- CaltechAUTHORS:20160719-120733646
- Getty Conservation Institute
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2016-07-25Created from EPrint's datestamp field
- Updated
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2021-11-11Created from EPrint's last_modified field
- Caltech groups
- Environmental Quality Laboratory