Actinic exposure film dosimetry: indicators of occupational exposure risk for office workers and school teachers

Actinic exposure film dosimetry: indicators of occupational exposure risk for office workers and school teachers

ICNIRP guidelines limit spectrally weighted (actinic) ultraviolet (UV) received by the unprotected skin or eye within an 8 hr period to 30 Jm-2. A technique for the calibration of miniaturised polyphenylene oxide (PPO) and polysulphone film dosimeters to the spectrally weighted actinic UV was employed in measuring occupational exposures received by school teachers and office workers for both short term (office workers) and long term (school teachers) applications. Short term polysulphone measurements (measured over several hours) found limited actinic exposures were received by office workers, while long term (weekly) exposure measurements using PPO film found that the recommended guidelines were routinely exceeded by school teachers as a consequence of yard and sport supervision duties. These findings raise important questions of balance for both occupational groups. Do school teachers need to modify their daily playground duties to limit the effects of potentially harmful exposure to solar UV and have office workers an accumulated solar safety budget as a result of spending long periods of time indoors and under the ICNIRP daily exposure threshold? The question of minimum recommended daily exposure and the need to optimise time in the sun due largely to the need to maintain personal vitamin D level is one that can be measured if the ICNIRP guidelines are taken as a maximum limiting value. This research presents preliminary actinic exposure measurements for both occupational groups and compares the upper actinic exposure limit with the corresponding vitamin D effective exposure.