Tag Archives: Noise

2088-2096 S. Kumar, J. Cerny and P. Kic
Air-conditioning in the cabins of passenger
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Air-conditioning in the cabins of passenger

S. Kumar*, J. Cerny and P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 21, Czech Republic
*Correspondence: surenderduhan88@gmail.com

Abstract:

The objective of this paper is to analyse the current state of the constructional design and operational conditions of air-conditioning device in passenger cars. The research was focused on the function of air-conditioning equipment of passenger cars Skoda and KIA in various modes of operation during the winter, spring and summer season at different levels of air conditioning (without air-conditioning, minimum, medium and maximum level). Air temperature, air humidity, globe temperature, CO2 concentration, dust concentration and noise inside the cabin were measured. Solar radiation plays a big role to rise up temperature inside the cabin. It resulted in the higher values of globe temperature than temperature of the air. The results of the measurements showed that CO2 values were significantly lower than 2,500 ppm at minimum air-conditioning, lower than 600 ppm at medium and lower than 500 ppm at maximum level of air-conditioning. For all vehicles, dust concentration was greater when it measured with the air conditioning switched off than with the air conditioning system turned on. The measurements confirmed that the total dust concentration was not more than 47 μg m-3, PM10 lower than 28 μg m-3 and PM1 lower than 27 μg m-3. The noise levels ranged from 49.1 to 68.7 dB(A). The air-conditioning had very positive impact on the inside comfort in car cabins from all points of view during all periods of the year.

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1300-1306 S. Kalle and J. Paju
Comparative study of the noise levels: impact of renovation
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Comparative study of the noise levels: impact of renovation

S. Kalle¹* and J. Paju¹²

¹Tallinn University of Technology, Tallinn School of Economics and Business Administration, Department of Business Administration, Academia road 3, EE12618, Tallinn, Estonia
²Tallinn University, School of Natural Sciences and Health, Narva road 25, EE10120, Tallinn, Estonia
*Correspondence: sigrid.kalle@ttu.ee

Abstract:

Health effects from different noise exposures have been studied by many researchers. According to the frequency of the noise, the complaints induced differ. Some studies have shown that low frequency noise may have serious health effects from annoyance to sleeping disturbances. Using a sound analyser with 1/3 octave band sound spectrum analysis capability, measurements were conducted on a scientific research vessel. Measurements were carried out in cabins, mess hall and engine room. The results were then compared to the Estonian and International Maritime Organization’s recommendations on noise as well as results from a previous study on the same vessel (previous study was conducted before the renovations to modernise both the engine and the cabins was conducted). The renovations did not have the desired effect on the overall noise levels of the vessel as a working environment; the noise values obtained after the renovations do not agree with the normative values during sailing. The situation has improved in several cabins on the vessel but the improvement is rather insignificant.

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895-906 K. Reinhold, S. Kalle and J. Paju
Exposure to high or low frequency noise at workplaces: differences between assessment, health complaints and implementation of adequate personal protective equipment
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Exposure to high or low frequency noise at workplaces: differences between assessment, health complaints and implementation of adequate personal protective equipment

K. Reinhold*, S. Kalle and J. Paju

Institute of Business Administration, Tallinn University of Technology, Ehitajate tee 5, EE12618 Tallinn, Estonia; *Correspondence: karin.reinhold@ttu.ee

Abstract:

Employees are exposed to high and low frequency noise which may cause different health effects. Hearing loss first occurs in the high frequency range, low frequency usually causes sleeping disturbances and annoyance. TES 1358 sound analyzer with 1/3 octave band was used to measure the equivalent sound pressure level, the peak sound pressure level, and the noise frequency spectrum at different workplaces. All the results were compared to Estonian and International legislations. High frequency noise was studied in metal, electronics and wood processing industries. The results showed that in several cases, the normative values were exceeded and the highest values appeared in the range of speech frequencies. Frequency analysis indicated that the noise level spectra at work stations of various machines differed in patterns. The low frequency spectra on a ship showed peaks in the frequency range of 50…1,250 Hz. Most employers provided workers with personal protective equipment against noise, but when selecting ear muffs, noise frequency had not been taken into consideration and therefore workers in the same enterprise used similar ear muffs. Knowledge of the prevailing frequencies assists to decide which ear protection should be used to avoid damage. An adequate hearing protector device can reduce the noise exposure significantly.

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251-260 P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle
Vibration and noise caused by lawn maintenance machines in association with risk to healt
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Vibration and noise caused by lawn maintenance machines in association with risk to healt

P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle

Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia;

Abstract:

The aim of this study was to compare vibration and noise characteristics caused by different types of lawn maintenance machines in association with the risk factors to workers’ health. In the present study, the method connecting vibration hazard, health damages and risk levels is presented. Three types of agriculture machines were investigated: all-terrain vehicles (ATV), simple lawn-mowers, ride-on mowers. These machines are used not only in occupational settings, but also by the inhabitants for cutting grass. The gardeners and maintenance workers of the municipal authorities use them daily, sometimes 8 hours a day. The protective equipment against noise is used in occupational settings, but hardly by the public. Noise was evaluated using a Sound Level Meter (TES 1358) following the standard ISO 9612:2009. Vibration was determined as acceleration, velocity and amplitude – measured using a Vibration Dosimeter & Analyser (SV 100) following the standards ISO 2631-4, EVS-EN 5349-2. The risk to the health is assessed by the original flexible risk assessment method worked out in TTU. On the basis of this flexible model the scheme for connecting the local and whole-body vibration hazards and possible health damages was worked out. The results showed that there are differences in the noise and vibration generated by the ATV, lawn-mowers and ride-on mowers. The safest was ride-on mower (local vibration below 1.15 m (s2 ) -1). Lawnmowers gave high vibration levels (over 3 m (s2 ) -1). The personal protective equipment (PPE) has to be worn by all users of the investigated machines. The noise spectral content by these three types of machines is presented and it is different. This enables to choose the right type of ear-muffs by the frequency of noise. The PPE against vibration is also available.

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