Regarding the outdoor behavior of the Caucasian population, modern sunscreens should provide high and broad-spectrum ultraviolet protection in the ultraviolet B as well as in the ultraviolet A range and should be photochemically stable for ultraviolet doses, which can be expected in solar radiation. At present an assessment of the photostability of suncare products is not a general requirement before marketing. In order to evaluate the photostability of suncare products we conducted an in vitro test and measured the spectral absorbance of 16 sunscreens before, and after exposure to increasing biologically weighted standard erythema doses (5, 12.5, 25, 50) of solar-simulated radiation. Seven of 16 suncare products showed a significant dose- and wavelength-dependent decrease of the ultraviolet A protective capacity, whereas the ability to absorb ultraviolet B was not affected. In the ultraviolet A range, the decrease of absorbance (photoinactivation), respectively, the increase of transmission was 12-48% for an ultraviolet exposure of 25 standard erythema dose. Photoinactivation started in the wavelength range between 320 and 335 nm with a maximum above 350 nm. Furthermore, our analysis showed that the behavior of suncare products was not predictable from its individual ingredients. Neither complex combinations of organic filters nor addition of inorganic filters could absolutely prevent photoinactivation. The inclusion of a single photounstable filter did not mean photoinstability of the complete suncare product. Photoinactivation of sunscreens appears to be an underestimated hazard to the skin, first, by formation of free radicals, second, by increased ultraviolet A transmission.

Optoelectronic personal UV-meters were used to monitor the occupational facial solar erythemally effective exposure of 12 Austrian full-time farmers with high temporal resolution. To ensure high quality measurements several quality assurance procedures were applied, like calibration with respect to solar elevation and total ozone column. From April to October the test persons carried the UV-meters on the forehead during working hours. A digital diary (activity, location, weather, photoprotective measures) was completed on an hourly basis. Our field test produced 1427 complete daily records (measurement and diary). The total exposures showed high variability (77-757 standard erythema dose [SED]) which correlates with the number of working days and even stronger with the little numbers of days with high exposure (>10 SED). Risk factors for high exposures were: mixed-culture farms with aggravated working conditions, low degree of automation of working processes, inadequate operating logistics (summarized as manual work outdoor), driving machines without cabins, and female gender. UV exposure of female farmers was approximately twice as high as that of men: Women received 15% of ambient radiation while men got 8%. Avoiding daily exposure >10 SED could reduce exposure down to 40% and the risk in developing skin cancer by a factor of 40.

In the mid-latitudes, pigs and poultry are kept predominantly in confined livestock buildings with a mechanical ventilation system. In the last decades, global warming has already been a challenge which causes hat stress for animals in such systems. Heat stress inside livestock buildings was assessed by a simulation model for the indoor climate, which is driven by meteorological parameters. Besides the meteorological conditions, the thermal environment inside the building depends on the sensible and latent energy release of the animals, the thermal properties of the building and the ventilation system and its control unit. For a site in Austria in the north of the Alpine Ridge, which is representative for confined livestock buildings for growing-fattening pigs in Central Europe, meteorological data between 1981 and 2017 were used for the model calculations of heat stress measures. This business-as-usual simulation over these 37 years resulted in an increase of the mean relative annual heat stress parameters in the range between 0.9 and 6.4% per year since 1981. In order to minimise the negative economic impact as the consequence of this positive trend of heat stress, adaptation measures are needed. The calculations for growing-fattening pigs show that such a simulation model for the indoor climate is an appropriate tool to determine the level of heat stress of livestock inside confined livestock buildings.

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The body surface area of man is the relevant receiving surface for solar UV radiation. To consider this body surface geometry, the biologically-effective UV radiation of the solar global radiation was measured. This was done at 26 differently aligned measuring points whose orientation was determined by the angle of inclination (vertical) and the azimuth (horizontal). Approximately eight hundred sets of measurement series were carried out at 33 different sites. A simple model, developed from the data obtained, made it possible to calculate relative irradiance as a function of the angle of inclination and the ground reflection (UV albedo). Thus relative risk of solar UV exposure to different regions of the body can be assessed. In addition to this, if the irradiance on a horizontal plane (measured or calculated by a corresponding model) is taken into consideration, the absolute values for UV irradiance on tilted planes can be determined.