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Queensland, Australia has one of the highest rates of skin cancer in the world. Outdoor workers are regularly exposed to high doses of ultraviolet radiation, and are at increased risk to develop non-melanoma and melanoma skin cancers. In 2010, a health promotion intervention to improve sun protection among outdoor workers in Queensland commenced. The intervention employed a mixed methods approach and a participatory action research framework. Fourteen workplaces were recruited from building and construction, rural and farming, local government, and public sector organisations. Management and workers were engaged in cycles of assessment, reflection and discussion, planning, implementation and reassessing, over a 14-month intervention period. Overall, at least one workplace representative from each workplace (range 1-3) and in depth focus groups were held with a subset of workers (range 3-16) to assess sun safe behaviours pre and post intervention. Workers’ attitudes, beliefs, knowledge and willingness to engage in sun protection differed depending on workplace characteristics and support. A familiar theme among workers spoke of sun safety as being “common sense” and the “workers individual responsibility”. Often there was a discrepancy in the perceptions of the workers, compared to the view of workplace representatives and the workplaces position or policy on sun safety. In larger workplaces, especially Government Departments, workers were more aware and followed sun safe practices compared to smaller workplaces where sun safety was not a high priority. These results indicate that a workplace culture which places high values on safety and polices more broadly may also have a positive effect on sun safety among outdoor workers as well. In addition, the specific characteristics of the workplace and the outdoor work tasks influence workers willingness to engage in sun safety measures.

Vitamin D production in the skin by UV exposure is the most prominsing means of alleviating the worldwide burden of vitamin D deficiency. However, we demonstrate that vitamin D production cannot be quantified by the current UV Index, which is based on the erythemal action spectrum. Large disagreement was observed when comparing (by computer simulation) the daily levels of erythemal UV and UV weighted for the established vitamin D action spectrum. We suggest that by using this spectrum, and accounting for other factors that affect vitamin D UV levels, a "Vitamin D Index" could be created. This could give more appropriate UV exposure advice than the current erythemal UV index alone, and reduce the worldwide burden of vitamin D deficiency.

We present data describing various techniques that operators of Brewer spectrophotometers can use to monitor and maintain the long-term performance of their instrument. The National Ultraviolet Monitoring Center (NUVMC) at the University of Georgia (UGA) operates, under contract from the U.S. Environmental Protection Agency (EPA), 21 Brewer spectrophotometer instruments. Due to the remote location of the instruments, constant monitoring of instrument performance is required to ensure that the instruments' performance does not deteriorate, hence impacting on data collection and quality. These techniques are illustrated with data from the Brewer instruments in the UGA/EPA network. © 2005 Society of Photo-Optical Instrumentation Engineers.

Queensland has the highest rates of non-melanoma skin cancer and cutaneous malignant melanoma in the world. Overexposure to ultraviolet (UV) radiation, particularly in childhood and adolecent years is a major risk factor in the development of skin cancer. South east Queensland's low latitudes and relatively clear skies combine to give high levels of solar UV. Simple UV protective measures such as wearing a hat can reduce the UV exposure of humans significantly. This paper will quantify the effect of UV protective devices, in particular hats and also quantify the UV exposure of schoolchildren during the times of day spent outdoors with and without a hat. Results are presented on the effect of the style of hat worn on the facial UV exposure to schoolchildren in Toowoomba.

Schoolchildren in south east Queensland, Australia are potentially exposed to high levels of solar ultraviolet (UV) radiation. However, little data has been collected on the amount of the annual UV exposure schoolchildren may receive whilst at school and the overall protectiveness of items such as hats. In this present study, the highest recorded lunchtime meal break UV exposure on a horizontal plane was 6 MED (minimal erythemal dose) in a 45 minute meal break in summer during February. For the same time period the highest UV exposure on the nose was 1.5 MED. The annual UV exposure of schoolchildren to the nose could be reduced by up to 50% if a hat were to be worn at all times whilst outdoors. This study also presents information on the UV exposure during various meal breaks and school sporting activities.

The annual solar UVA exposures in four cars were estimated by measuring the UVA irradiances in the vehicles in each of the four seasons and in the morning, noon and afternoon. For the cars with untinted windows the maximum UVA irradiances in cars do not necessarily occur at noon when the outside irradiances are at their highest. Additionally, they do not occur in summer. The range of annual UVA exposures between 9:00 and 15:00 EST is 1918 to 6177 J cm-2 for the cars without the after market window tint. These correspond to 5% to 17% of the ambient UVA on a horizontal plane over the same period outside the cars. The range is for the different sites in the car. For the car with the aftermarket window tint, the range of the annual UVA exposures were 489 to 2969 J cm-2 or 1% to 8% of the ambient UVA.

This paper has provided the first set of quantitative data of diffuse erythemal UV and UVA in tree shade at a sub-tropical Southern Hemisphere latitude. Over the summer, approximately 60% of the erythemal UV radiation in the tree shade is due to the diffuse component. Similarly, approximately 56% of the UVA radiation in the tree shade is due to the diffuse component. In the tree shade these diffuse UV percentages are relatively constant from the morning to noon to afternoon periods. In comparison, in full sun, there is a decrease in the percentage diffuse UV from morning to noon to afternoon. The exposures to diffuse UV on a horizontal plane in the tree shade between 9:00 EST to 15:00 EST were of the order of 4 MED and 14 J cm-2 for erythemal UV and UVA respectively. The high diffuse UV component in the shade may result in high UV exposures to not only parts of the body on a horizontal plane that are not protected, but also, equally high UV irradiances to parts of the body, including the eyes and face, that are not UV protected.

The personal radiant exposure distribution of solar erythemal UV in tree shade for an upright posture was measured, with measurements over the whole summer for a total of seventeen trees. For each tree, the personal radiant exposure distribution was measured for both the morning and afternoon periods. The exposure ratios averaged over all the trees and over the morning and afternoon periods ranged from 0.16 to 0.49 for the different anatomical sites. A numerical model was employed to estimate the UV radiant exposure to humans in the tree shade over the entire summer. The body sites with the higher exposure ratios in the tree shade were the vertex of the head, shoulders and forearms with radiant exposures over the summer of 1,300 MED to the vertex of the head and 1,100 MED to the shoulders and forearms. These radiant exposures in the shade are substantially higher than the ambient erythemal UV measured in full sun on a horizontal plane over a full summer at a more temperate Northern Hemisphere latitude. The average radiant exposures per day to each anatomical site for a complete day in the tree shade ranged from 4.6 to 14.6 MED. The research has provided new data that is essential to quantify the human UV exposure during outdoor activities.

The research in this paper quantifies the solar erythemal UV exposures to the skin through a common summer garment during outdoor activities. The erythemal exposures under the garment for the wet white garment exceeded a MED (minimum erythemal dose) at some anatomical sites in summer for a two hour period. An erythemal exposure of 1.7 MED, in excess of the occupational limit for UV exposure, was measured under the white garment during swimming for a one hour period. Clothing must form an important component of a UV protection strategy. However, it must be realised that total UV protection is not provided and significant UV exposures may be received beneath the garment, particularly for a white garment in the wet state. This re-enforces the necessity of a combination of several UV prevention strategies to minimise UV exposure.

Evidence from epidemiological research suggests that childhood exposure to solar ultraviolet (UV) radiation is an important causative factor in the formation of skin cancer. A mathematical model was employed to investigate the effect of meal break times on solar UV radiation exposure to schoolchildren in Southeast Queensland for the month of February. The model incorporates UV irradiances measured continuously during daylight hours for a summer month in Toowoomba (27.5o S latitude) along with the anatomical distribution of UV to specific body sites measured with polysulphone UV dosimeters. The polysulphone dosimeters have a UV response approximating that of human skin and are calibrated for UV exposure against a calibrated spectroradiometer. This paper presents the results of the UV exposures to the nose, chin, forehead and forearm for different meal break times in schools. These UV exposures were reduced by a factor of up to 0.8 by varying the school meal break times alone. Optimisation of the existing morning and lunch break times reduced the UV exposures in the school day by a factor of up to 0.45. Results of extrapolating these results to the whole year will be discussed.

The dependence of the spectral biologically effective solar UV irradiance on the orientation of the receiver with respect to the sun has been determined for relatively cloud-free days at a sub-tropical Southern Hemisphere latitude for the solar zenith angle range 35-64 degrees. For the UV and biologically effective irradiances, the sun-normal to horizontal ratio for the total UV ranges from 1.18 +/- 0.05 to 1.27 +/- 0.06. The sun-normal to horizontal ratio for biologically effective irradiance is dependent on the relative effectiveness of the relevant action spectrum in the UV-A waveband. In contrast to the total UV, the diffuse UV and diffuse biologically effective irradiances are reduced in a sun-normal compared with a horizontal orientation by a factor ranging from 0.70 +/- 0.05 to 0.76 +/- 0.03.

The solar spectral UVR irradiances in tree shade and sunlight have been measured in a sub-tropical Southern Hemisphere summer. The spectral data allowed the UVB and UVA irradiances and the biologically effective irradiances to be calculated for different harmful biological processes to human skin and eyes. The average of the ratio of the UVA to UVB irradiances was lower by 26% in the shade compared to the same ratio in the sun. The spectral shade ratio calculated as the ratio of the spectral biologically effective irradiances in the shade to those in the adjacent sun decreased with increasing wavelength for all of the trees. The decrease in the shade ratio was approximately 42% at 400 nm compared to the shade ratio at 300 nm. Despite the UVR protection provided by tree shade, the erythemal UVR exposure received in one hour in the tree shade exceeded the occupational limit for UVR exposure.

This paper presents the variations in the solar erythemal ultraviolet (UV) exposure during work hours due to daylight saving time in Australia. The differences in the exposures to workers on AEST (Australian Eastern Standard Time) and AEDT (Australian Eastern Daylight Time) are dependent on the meal break times and the morning and afternoon tea break times. There were both increases and decreases in the erythemal UV exposures to the workers. For the shoulder of workers outside between 07:00 and 17:00 who take a meal break out of the sun, the largest decrease provided by switching to AEDT was 118 MED (minimum erythemal dose) over the five month period for the 12:30 to 13:30 AEST break time. In comparison, the maximum increase for the shoulder was 29 MED for the 11:00 to 12:00 AEDT break time. For indoor workers who spend a meal break outdoors, the maximum increase was by 49 MED over the five months on a horizontal plane for the 12:30 to 13:30 AEST break by converting to AEDT. In comparison, for the 11:00 to 12:00 AEST meal break time, the erythemal exposure was decreased by 58 MED by converting to AEDT. The results are also applicable to locations that are west of the coastal cities where the sunrise and sunset times are later.

Taking sun sheltered meal and tea breaks around solar noon can reduce occupational exposure to solar erythemal ultraviolet (UV) radiation by outdoor workers. The research presented in this paper has quantified the reductions in solar UV exposure to be expected in summer and winter for different scenarios of break times for this high UV exposure occupational group of the population.

The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradiances at various locations within four different makes of car and a tractor were also measured with a broad band UVA hand-held meter. The average normalized daily UVA exposure (measured with a broad band UVA meter) was 1.3 times higher in a large family sedan when compared with that in a small hatchback and the UVA exposure in a car with tinted windows was 3.8 times less than in a similar untinted car.

The spectral ultraviolet (UV) transmission through stockings was measured in field and laboratory based trials using a spectroradiometer. From these spectral UV measurements, the ultraviolet protection factor (UPF) was calculated. The UPF of stockings measured in the field was generally higher than that measured in the laboratory when using a quartz tungsten halogen light as the UV source. The UPF of 50 denier stockings decreased 868% when stretched 30% from their original size. Doctors recommending and patients using high denier stockings for patient photoprotection should be aware of the dramatic decrease in UPF when the stocking is in a stretched position, such as over a human leg.

An experiment is described to expose students in a ‘hands-on’ manner to the physics of instrumentation, measurement, electromagnetic radiation and in particular UV radiation. The students will have no difficulty in setting up the apparatus themselves and they will obtain reliable results within a normal school practical period. Additionally, the students will undertake a scientific experiment relevant to everyday life.

The experiment described in this paper provides students the opportunity to study the Physics of electromagnetic radiation and its interaction with the physical environment and also illustrates that Physics exists outside the school laboratory. The amount of solar ultraviolet radiation in tree shade is measured at different times of the day and compared with changes in illumination levels and temperature.