Variability among polysulphone calibration curves

Abstract

Within an epidemiological study regarding the correlation between skin pathologies and personal ultraviolet (UV) exposure due to solar radiation, 14 field campaigns using polysulphone (PS) dosemeters were carried out at three different Italian sites (urban, semi-rural and rural) in every season of the year. A polysulphone calibration curve for each field experiment was obtained by measuring the ambient UV dose under almost clear sky conditions and the corresponding change in the PS film absorbance, prior and post exposure. Ambient UV doses were measured by well-calibrated broad-band radiometers and by electronic dosemeters. The dose-response relation was represented by the typical best fit to a third-degree polynomial and it was parameterized by a coefficient multiplying a cubic polynomial function. It was observed that the fit curves differed from each other in the coefficient only. It was assessed that the multiplying coefficient was affected by the solar UV spectrum at the Earth's surface whilst the polynomial factor depended on the photoinduced reaction of the polysulphone film. The mismatch between the polysulphone spectral curve and the CIE erythemal action spectrum was responsible for the variability among polysulphone calibration curves. The variability of the coefficient was related to the total ozone amount and the solar zenith angle. A mathematical explanation of such a parameterization was also discussed.

Personal UV exposure in high albedo alpine sites

“…This curve can be determined in situ or it can be derived once total ozone and solar zenith angle are known, in order to take into account the local environmental conditions of the site (Casale et al, 2006). Three sites at different altitude were chosen in order to investigate the variability of PS calibration curves: the lowest site of Saint Christophe, at Les Grange and at La Thuile-Les Suches ski field.…”

“…It should be kept in mind that the limit of polysulphone dosimetry is that it does not allow to record individual personal doses differently from photoelectronic captors. The PS methodology requires a careful quantification of the calibration curve (ambient dose versus PS film absorbance changes prior and post exposure) nearby the site under investigation (Casale et al, 2006). Although somewhat variability was observed among the c values of calibration curves at the different altitude sites, an average altitude of 2100 m a.s.l.…”

Extreme UV index and solar exposures at Plateau Rosà (3500 m a.s.l.) in Valle d’Aosta Region, Italy

“…The dosimetric calibrations were carried out on August 9 th characterized by similar total ozone amounts compared to July 12 th . This parameter together with the solar zenith angle is the main factor affecting the variability of the calibration curves (Casale et al, 2006). Rome was also included in the dosimetric calibration campaign as an additional geographical location because of its peculiar environmental features as an urban site at lower latitude.…”

“…(1)) for the 40 μm thick PS dosimeters is a polynomial function usually expressed as the product of a calibration factor and a fixed third-degree polynomial of the absorbance change (e.g. Casale et al, 2006). The functional form of the PS response expressed by the cubic fit was theoretically explained by Colucci (2007).…”

Long-term UV dosimeter based on polyvinyl chloride for plant damage effective UV exposure measurements

“…The variation within one standard deviation of the mean for this UV 245 during the peak UV times is ±12%. This variation has been addressed in this research by 246 calibrating the dosimeters at the site and for the atmospheric conditions of the measurement 247 dosimeters (Casale et al, 2006). evaluated as ±16% using the technique described in Amar (2014 (http://giovanni.gsfc.nasa.gov/giovanni/).…”