Journal of Health and Safety at Work

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Introduction: Exposure to vibration as one of the consequences of industrial noise or the use of vibration generators can cause discomfort, reduce the efficiency and level of safety in workplaces. Therefore, in this study, the effect of whole body vibration on individual’s mental performance and response time was investigated.

Material and Method: In this study, 40 male students of Tehran University of Medical Sciences were selected randomly and divided into two 20 subjects groups. Each group participated in two Pegboard Board and Math Calculations tests. Subjects in each stage of test were exposed to whole body vibration with acceleration in 0.8 and 1.1 m/s2 as well as background mode without vibration and were investigated response time and mental performance.

Result: In the present study, the mean response time to the manual Purdue Pegboard test in the vibrational acceleration of 0.0, 0.8 and 1.1 m/s2 with a decreasing trend was 197.55 ± 2.7, 176.25 ± 5.38 and 177.58 ± 2.92, respectively, which results in a significant reduction in the accuracy of the test. Also, the results showed that whole body vibration does not affect mental performance in shallow levels. But, in the intermediate and deep levels, this difference is statistically significant (p <0.001).

Conclusion: Based on the results, whole body vibration is an effective factor in individual’s response time and mental performance, which can lead to a reduction in the accuracy of the work.

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Introduction: The skin, can be exposed to harmful factors like ultraviolet radiation (UV). Exposure to this physical hazardous agent could be contributed to pigmentation, erythemas, early aging, skin cancer, and DNA damage. The aim of this study, therefore, was to fabricate the polyacrylonitrile (PAN) nanofibers with the UV protection property by the use of various concentrations of titanium dioxide (TiO2) nanoparticles.
Material and Methods: The PAN nanofibers (10%wt) containing 0, 1, 5, 10 and 15% wt of TiO2 nanoparticles were produced using electrospinning method. The morphological propertis of nanofibers were studied by scanning electron microscopy (SEM) and the functional groups were investigated by Fourier transform infrared spectrophotometer (FTIR). The UV protection property of nanofibers was studied by measuring UV transmittance as well as calculating UV protection factor (UPF).
Results: The results showed that the diameter and morphological characteristics of nanofibers are different at various concentrations of TiO2 and increasing the concentration of TiO2 has resulted to an increase in nanofibers diameter. The analysis of FTIR results showed that TiO2 nanoparticles have been successfully loaded on nanofibers for UV protection purposes. The findings clarified that nanofibers loaded with TiO2 could increase the UV protection property up to 15%.
Conclusion: Totally, our findings show the successful fabrication of UV-protective nano webs using TiO2 nanoparticles. the new combination used in nano matcould protect employees from UV radiation.