A New, Portable, Real-Time Ozone Monitor

详细信息    查看全文

• 作者：Douglas R. Black ; Robert A. Harley ; Susanne V. Hering ; and Mark R. Stolzenburg
• 刊名：Environmental Science & Technology
• 出版年：2000
• 出版时间：July 15, 2000
• 年：2000
• 卷：34
• 期：14
• 页码：3031 - 3040
• 全文大小：111K
• 年卷期：v.34,no.14(July 15, 2000)
• ISSN：1520-5851

文摘

New methods are needed to assess microenvironmentaland personal exposures to ozone. A real-time ozone sensorusing a piezoelectric quartz crystal has been developedand evaluated. The crystal is coated with polybutadienewhich reacts irreversibly with ozone, resulting in a massincrease on the surface of the crystal which, in turn, altersits natural oscillation frequency. The rate of change infrequency is proportional to the concentration of ozone andis recorded by a datalogger with a time resolution of 10min. Experiments were conducted to investigate sensorresponse, useful lifetime, and potential interferences. Monitorcomponents such as a pump, power supply, and dataloggerwere arranged to fit within a compact enclosure. Fiveprototype ozone monitors were assembled and evaluatedin the laboratory and in a field study of two offices andtwo residences in Southern California. Field measurementsmade with two quartz crystal-based ozone monitorsexhibited precision ranging from 6 to 27% (13% on average)and bias ranging from -37 to 2% (-13% on average)when compared to a reference method (UV photometricdetection) for real-time ozone measurement. The monitorhas a sensitivity of 3 ppb ozone (limit of detection for S/N =3) and a useful lifetime of ~20 h at an average ozoneconcentration of 50 ppb (1000 ppb-h). This prototype monitoris smaller, lighter, and more affordable than existing UVozone analyzers and with further development may be suitablefor real-time personal ozone monitoring.