A Reference UV-B Spectroradiometer For Comparison And Auditing of Field Monitoring Instruments

Abstract

As part of the Environmental Protection Agency's stratospheric ozone program, the Atmospheric Research and Exposure Assessment Laboratory of the EPA (AREAL) has been given the responsibility of standardizing absolute measurements of incident ultra-violet radiation being obtained by various environmental research activities, both within and outside of EPA. Of primary interest are quantitative UV radiation flux measurements in the environmentally active wavelength range of 280 to 400 nm, including the UV-B range. Measurements of UV-B radiation are associated with a wide variety of research activities endeavoring to quantitatively relate exposure to incident UV radiant energy intensity - particularly changes or effects on human health and on the various environmental ecosystems. A significant amount of UV-B measurement activity in the scientific community is currently underway or is being planned. Currently, many of the UV-B measurements suffer from substantial lack of comparability and credibility due to wide variations in the quality and calibration accuracy of the UV-B measurement instruments used. To ensure that measurements throughout these activities are of known quality, a quality assurance program should be developed. One of the first steps to ensure known data accuracy is to establish a measurement standard for the monitoring instrumentation.