Frequency weighting to evaluate the feeling of pressure and/or vibration caused by low-frequency noise: Re-analysis of an existing study

Low-frequency noise may create specific perceptions, which might cause various health effects. The present study aimed to identify exposure–response relationships between low-frequency noise and perceptions by re-analysing an experimental study. We investigated the predominant perceptions of ‘feeling bothered’ and ‘feeling of pressure and/or vibration’ using multivariate logistic regression analysis. A significant interaction between 1/3 octave-band sound pressure level and frequency was indicated for ‘feeling bothered’ but not ‘feeling of pressure and/or vibration’, suggesting that the ‘feeling of pressure and/or vibration’ does not originate in cochlear. A mathematical model indicating resonance at approximately 50 Hz fitted the results well. A frequency weighting derived from the mathematical model could be applied to broad-band low-frequency noise to evaluate the perception and health effects. However, further investigations on the weighting for the perception are necessary because the results were obtained only from the existing study.

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A Study on Exhaust Muffler Using Counter-Phase Counteract

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.986-987.810 ◽

2014 ◽

Vol 986-987 ◽

pp. 810-813

Author(s):

Ying Li Shao

Keyword(s):

Mathematical Model ◽

Experimental Validation ◽

Noise Source ◽

Low Frequency ◽

Frequency Noise ◽

Expansion Chamber ◽

Band Noise ◽

Exhaust Noise ◽

Perforated Pipe ◽

The Mathematical Model

The exhaust noise, which falls into low-frequency noise, is the dominant noise source of a diesel engines and tractors. The traditional exhaust silencers, which are normally constructed by combination of expansion chamber, and perforated pipe or perforated board, are with high exhaust resistance, but poor noise reduction especially for the low-frequency band noise. For this reason, a new theory of exhaust muffler of diesel engine based on counter-phase counteracts has been proposed. The mathematical model and the corresponding experimental validation for the new exhaust muffler based on this theory were performed.

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Potential health effects of standing waves generated by low frequency noise

Noise and Health ◽

10.4103/1463-1741.113518 ◽

2013 ◽

Vol 15 (65) ◽

pp. 237 ◽

Cited By ~ 2

Author(s):

Stanislav Ziaran

Keyword(s):

Health Effects ◽

Standing Waves ◽

Low Frequency ◽

Frequency Noise ◽

Low Frequency Noise ◽

Potential Health

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Infrasound and Low Frequency Noise in the Passenger Compartment of Vehicles

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/026309239701600401 ◽

1997 ◽

Vol 16 (4) ◽

pp. 219-227 ◽

Cited By ~ 1

Author(s):

Helmut Spannheimer ◽

Raymond Freymann

Keyword(s):

Mathematical Model ◽

Low Frequency ◽

Experimental Investigations ◽

Frequency Noise ◽

Simple Mathematical Model ◽

Low Frequency Noise ◽

Acoustic Response ◽

Frequency Range ◽

Passenger Compartment

The acoustic response determined in the passenger compartment of a vehicle is characterized by resonances in the infrasound and low frequency range. A simple mathematical model is derived allowing the numerical identification of the related low frequency acoustic eigenmodes. The numerically obtained results are verified on the basis of experimental investigations.

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Study of the physiological and mental health effects caused by exposure to low-frequency noise in a simulated control room

Building Acoustics ◽

10.1177/1351010x18779518 ◽

2018 ◽

Vol 25 (3) ◽

pp. 233-248 ◽

Cited By ~ 6

Author(s):

Ali Mohammad Abbasi ◽

Majid Motamedzade ◽

Mohsen Aliabadi ◽

Rostam Golmohammadi ◽

Leila Tapak

Keyword(s):

Mental Health ◽

Working Memory ◽

Health Effects ◽

Cognitive Performance ◽

Low Frequency ◽

Mental Fatigue ◽

Frequency Noise ◽

Low Frequency Noise ◽

Control Rooms ◽

Mental Health Effects

The purpose of this study was to investigate the physiological and mental health effects caused by exposure to low-frequency noise in typical control rooms and office-like areas. The participants were 35 male students who were exposed to noise at levels of 55, 65, 70, and 75 dBA. The N-back test was used at three cognitive performance loads (low workload ( n = 1), medium workload ( n = 2), and high workload ( n = 3) to evaluate working memory simultaneously in an air conditioning chamber in four sessions with a constant level. The electroencephalography, electrocardiogram, and electrooculography were measured using Nexus 4 by Bio traces software (Mind Media Co.). For evaluation of mental fatigue, fatigue visual analog scale, and psycho-physiological indices were also used. The results showed that the losses of physiological and mental health were rapidly increased with exposure to noise levels of 65–75 dBA. The results showed that mental fatigue significantly affected heart rate, low- to high-frequency ratios, and electroencephalogram indices such as theta, alpha, as well as eye activities and working memory. The findings confirmed that the mental fatigue caused by low-frequency noise significantly impacted the employees’ psycho-physiological and working memory responses. Implementation of the effective interventions to overcome employees’ mental fatigue in typical control rooms and office-like areas can improve the health and acoustic comfort and, consequently, the cognitive performance.

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On the Low Frequency Noise Assessment Method

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1260/026309203322770301 ◽

2003 ◽

Vol 22 (2) ◽

pp. 53-61 ◽

Cited By ~ 1

Author(s):

Paolo Lenzuni

Keyword(s):

Low Frequency ◽

Assessment Method ◽

Frequency Noise ◽

Correction Factors ◽

Low Frequency Noise ◽

Synthetic Indicators ◽

Noise Annoyance ◽

Noise Assessment ◽

Frequency Weighting ◽

Frequency Weightings

A new assessment method for low frequency noise annoyance is proposed. A new frequency weighting is introduced, and its robustness tested. Possible effects of impulsiveness and tonality are discussed. The method proposed explicitly includes correction factors for the former, while the latter is shown to be insignificant in this context. The method is cross-checked with existing methods based on frequency weightings, and its performance is objectively quantified using synthetic indicators.

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