The paper describes a specific design of the sound insulating enclosure of a vibrating sorter. Recycling aspects have been taken into account when designing the enclosure, because recycled foam has been applied as a sound-absorbing material. An acoustic camera was used to measure, analyze, evaluate and to localise and identify sound sources. The visualization method was used to locate the critical locations of the device and then quantify them. To evaluate the effectiveness of the proposed enclosure, the measurements of the sound parameters were performed before and after the realization soundproofing measure. The measured results show the requested efficiency of the sound insulating enclosure in terms of noise reduction as well as dust near the sorter.

Currently, emphasis is still placed on risk evaluations of physical factors in workplaces. The aim of this paper was to evaluate objectively and subjectively the noise parameters and microclimate conditions near conveyor systems at the workplace for the handling and sorting postal items. Objective noise measurements were performed using the Norsonic 140 sound analyser, Class 1 and microclimatic conditions using the Testo 435 instrument. The subjective evaluation was performed by the questionnaire method (120; F: 66; M: 54). The result of the research was the assessment of health risks, depending on the sources of noise caused by conveyor systems.

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In modern society, humans spend most of their time in the indoor environment (home, work, school...). This indoor lifestyle constantly poses challenges to our physical and mental health by affecting our hormone levels and circadian rhythm. This article deals with the possible connection between human and working environment factors and the emergence of health problems in connection with work. Using statistical methods, the dependence between the six characteristics (age, length of employment, visual demand of the work task, satisfaction with lighting conditions, and shift work) and occurrence of health-related problems and discomfort (i.e., eye discomfort, headache, eye fatigue, and seasonal affective disorder symptoms) was examined. The paper also deals with the evaluation of lighting conditions in the workshop using the lighting design software DIALux evo 9.2. Using this software, two lighting variants were modeled. The first simulated variant included lighting parameters according to the currently used luminaries and the second variant contained more efficient LED luminaries.

Sound visualization tools are now widely used in industry. As a tool, acoustic cameras are also well-suited for faster identification of errors as well as individual states while operating devices. The aim of this paper was to locate and quantify noise sources on a packet sorting line using an acoustic camera and then to propose noise reduction measures. Localization of noise sources was performed by means of an acoustic camera with a microphone ring array. The result of these measurements and analyses was to sort the individual noise sources from less noisy to the noisiest, which gives a good assumption for better planning of spending on the implementation of noise reduction measures. The outputs of these measurements also give information on the character and frequency composition of the sound of individual sources, which will help out in the design of specific noise measures.

In terms of design and material composition, cars are the large set of diverse materials and raw materials. The relative proportion of materials varies along with the development and innovation of new types of cars. The most represented material is metal. On average, outdated cars feature about 8% of plastic and approximately 4% of rubber products. The problem is the further use of these recycled materials. The research has found new areas for the use of tires, waste foam and interior materials—noise reduction. The authors have designed and tested several variations of acoustic absorption materials. Of the tested materials, the best parameters were shown by “ecofoam”—almost across the entire frequency range (100–5000 Hz).

In acoustic practice, established methods of measuring the acoustic properties of partition structures are used. Recommended procedures and means can be found in technical standards, but practice suggests that measurement results may also depend on measurement conditions. These procedures leave the choice of noise type, frequency interval examined, and excitation interval on the measurer. The aim of this research is to determine which parameter has a significant effect on the results, and to quantify the extent of this effect. We examined the type of noise, the frequency band of the sound passing through the partition structure and the excitation interval of the diffusion field in the rooms (hereinafter referred to as “excitation interval”). During the research, we conducted a number of repeated, statistically significant measurements, which we first evaluated by classical methods used in acoustic practice. We subjected the obtained results to a thorough mathematical analysis. Evaluation of the results shows that some measurement conditions significantly affect the resulting values, especially in the low-frequency spectrum. One of the most important elements which has an effect on the results is the type of excitation noise, which, when assessed in the source room, excites the diffuse sound field, and its transmission through the considered partition structure is measured. The significance of the investigated frequency interval was also demonstrated.

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