Acoustical measurements suggest that for high frequency settings of the investigated design, sound was audible due to the presence of a faint but audible 45kHz component in addition to the high frequency components. 7 I have a pressing feeling in my ears, 15 During the test I could not concentrate on what I was doing. In this way, possible contributions of the background noise to the determined SPL were discarded. 2021 Dec 16;18(24):13289. doi: 10.3390/ijerph182413289. 3b If yes, did it sound nice, neutral, unpleasant, very unpleasant? First, the SPLs of the Kemo-device, type M175-02-18, without and with the external L020 loudspeaker, were determined for frequencies ranging between 20Hz and 46kHz (experiment 1). Phone: (414) 438-8420, 1828 East Wisconsin Ave. Clark, C.,
We tried noise abatement measures for displeasure people. Brozoski, T.,
The (symmetrical) pinna and orientation of the head with respect to the connecting line between the head and the source influence the effective sound level. The background noise level in this semi-anechoic room was less than 0dB SPL. The study was approved by the Medical Ethical Committee of the University Hospital Leuven (B322201318943). Paulin, J.,
Rodriguez Valiente, A.,
, Effects of ultrasonic noise on the human bodyA bibliographic review, 36. Holm, S., and
In order to scale the amplitude of the signals and spectra, a reference wave file was recorded while placing the microphone in a 1kHz, 94dB SPL calibrator, using the same settings for the hardware and data processing. J Acoust Soc Am. The directivity of the source for setting 5, with emission in the 1214kHz range, is shown in Fig. Dhar, S.,
Pelanova, J.,
Look for holes in the exterior of your home, especially where cables or pipes enter your home. Sivaraman, K. (2016). Popelar, J.,
, Ueda, M.,
C. Spectral content of the very high frequencies and ultrasounds. Sun Prairie, WI 53590 microphone B&K (Brel & Kjaer, Naerum, Denmark) type 4138 (flatness of 1dB between 20 and 50000Hz). Spectral analyses showed that, besides emitting frequency modulated sounds in the expected frequency ranges, a faint but audible sound in the 45kHz range was present. Brozoski, T.,
Their responses did not differ from the average data. , High-frequency hearing thresholds: Effects of age, occupational ultrasound and noise exposure, 13. During exposure the subject was allowed to read or use a tablet. Perez-Diaz, F.,
ter Haar, G. (2012). Humans and pets, however, cannot hear them. DeGomez, T. (2014). For each scenario of interest, a recording was made and analyzed spectrally. Matheson M. P. (2003). Takahashi, H. (2014a). Scapellato, M. L.,
Zecker, S., and
In the first approach, the measurement microphone was positioned at 6.5m from the loudspeaker(s), i.e., at 0.5m within the distance used during the perceptual tests. McLoughlin, I. V.,
The Journal of Wildlife Management contains information from original research that contributes to the scientific foundations of wildlife management. Pelanova, J.,
Janssen, S., and
(2015). It was verified by the experimenters that this 45kHz sound component, whose existence is not mentioned in the device specifications and is unintentionally produced by the device, was always present, albeit fluctuating in frequency and magnitude. , High-frequency pure-tone audiometry in children: A test-retest reliability study relative to ototoxic criteria, 39. This was done using a portable high frequency audiometer [Orbiter 922 version 2, Madsen Electronics (Orbiter, Budapest, Hungary)] and a Sennheiser HDA200 circumaural headphone (Sennheiser, Wedemark, Germany). So, do ultrasonic rodent repellents really work? Veuillet, E.,
Jastreboff, M. M. (2015). Popelar, J.,
They were recruited through personal contacts, flyers, the Federal Public service Health intranet and Facebook page. SPLs were also measured with a microphone of a Head Measurement System (Head Acoustics) with the microphone cap just below and at 1cm distance from the opening of the ear canal, in order to assess the acoustical head shadow effect. ter Haar, G. (2012). Cacace, A. T.,
When the signal was perceivedand this occurred more frequently with the two lower frequency settings and with two sourcesit was considered to be disturbing by several participants. (2012). , Paulin, J.,
Sivaraman, K. (2016). Some of these spots are large enough for mice to sneak through. (2014). , Jastreboff, P. J., and
Martin, N., and
Hooiveld, M., and
, Decreased sound tolerance: Hyperacusis, misophonia, diplacousis, and polyacousis, 21. , Chopra, A.,
Settings lower than 5 were not included, as their respective frequencies were clearly in the audible range, and expected to be perceived as even more disturbing than the tested ones, especially with two sources on (or with one source at a shorter distance from the subject). Given the increasing usage of ultrasonic devices as well as the much longer exposure of high frequency and ultrasound in domestic usage, careful consideration and better guidelines are required, especially for those who are most sensitive to sound. Collet, L. (2002). Selecting this option will search all publications across the Scitation platform, Selecting this option will search all publications for the Publisher/Society in context, Exposure to wind turbine noise: Perceptual responses and reported health effects, Long-term effects of noise reduction measures on noise annoyance and sleep disturbance: The Norwegian facade insulation study, Assessment of noise measurements made with a continuous monitoring in time, Short-term annoyance reactions to stationary and time-varying wind turbine and road traffic noise: A laboratory study, Long-term road traffic noise exposure is associated with an increase in morning tiredness, Audio-visual interaction and perceptual assessment of water features used over road traffic noise, Exposure-response relationships for annoyance due to freight and passenger railway vibration exposure in residential environments, A procedure for the assessment of low frequency noise complaints, Effects of very high-frequency sound and ultrasound on humans. For this reason, ultrasonic rodent repellents are highly appealing to homeowners for the proclaimed ability to repel rodents from overstaying their welcome. Davis, A.,
2021 Nov 8;8:760845. doi: 10.3389/fvets.2021.760845. II. Groh, D.,
Takahashi, H. (2014b). Jilek, M.,
Dolder CN, Fletcher MD, Lloyd Jones S, Lineton B, Dennison SR, Symmonds M, White PR, Leighton TG. Bartolucci, G. B. Brink, M.,
Scapellato, M. L.,
Lee J, Dhar S, Abel R, Banakis R, Grolley E, Lee J, Zecker S, Siegel J. , Changes in otoacoustic emissions and high-frequency hearing thresholds in children and adolescents, 15. 
, Jilek, M.,
Founded in 1807, John Wiley & Sons, Inc. has been a valued source of information and understanding for more than 200 years, helping people around the world meet their needs and fulfill their aspirations. Basner, M.,
Data were analyzed anonymously. Subsequently, the subject responded to items 415 on a Likert scale. High-Frequency Audiometry in Women with and without Exposure to Workplace Noise. Keiner, A. J.,
van Kamp, I.,
If your rodent problem continues to persist, call in an expert. Ota, A., and
Dauman, N.,
For terms and use, please refer to our Terms and Conditions Banakis, R.,
With settings 8 and 9, however, the presence of the 45kHz signal component that accompanied the ultrasonic 2528kHz signal, was found disturbing by several persons. Lanser, J. J. , Lee, J.,
PMC For instance, we are aware of clinical significant hyperacusis occurring in approximately 1.75% of the general population (, Children form another important demographic subset within the population. , Dahl, T.,
, Auditory and non-auditory effects of noise on health, 34. Carrieri, M.,
, Andringa, T. C., and
Heres the breakdown. Tyler, R. S.,
Dauman, N.,
Give us a call or contact us online for an inspection and plan of action. , Bio-effects and safety of low-intensity, low frequency ultrasonic exposure, 33. The spark source and microphone were placed at about 13cm above the soil covered by grass and about 30cm from each other. Bang, H. J.,
To the mouse, the frequencies will sound like a loud jackhammer. 
Ultrasonic rodent repellents are small devices that emit high-frequency sound waves that are claimed intolerable to rodents. Chung, S.,
MeSH Mohan, K., and
(2012). Trevisan, A., and
With a growing open access offering, Wiley is committed to the widest possible dissemination of and access to the content we publish and supports all sustainable models of access. Wiley has published the works of more than 450 Nobel laureates in all categories: Literature, Economics, Physiology or Medicine, Physics, Chemistry, and Peace. Mohan, K., and
, Investigation on high-frequency noise in public space, 37. Selecting this option will search the current publication in context. . Baliatsas, C.,
, Tyler, R. S.,
Andersson, G.,
Here are a few reliable prevention methods: Contact Wil-Kil for Effective Rodent Control. Kabelka, Z., and
The addition of the external loudspeaker resulted in an increase of 3dB (Table, Hearing thresholds were determined separately of the left and right ear for frequencies between 1 and 16 kHz to ensure normal hearing. and transmitted securely. Acton, W. I., and
Pre-exposure: Thresholds for high frequency sinusoids were obtained before commencing the perceptual experiment, and participants responded to items 414 of the survey in order to have a baseline. (1967). official website and that any information you provide is encrypted Grigg EK, Chou J, Parker E, Gatesy-Davis A, Clarkson ST, Hart LA. Items 1 and 2 were scored as yes/no and only administered once, prior to commencing exposure. Maso, S.,
Suitable topics include the results and interpretations of investigations into the biology and ecology of wildlife that can be used for management. In order to assess the effect of reflections in a garden setting, we also determined the high frequency sound reflection coefficient of soil covered by grass. Syka, J. Wiley is a global provider of content and content-enabled workflow solutions in areas of scientific, technical, medical, and scholarly research; professional development; and education. B&K 4231 1kHz, 94dB SPL calibrator for reference calibration. Some homeowners have noted an immediate effect at first, but over time the rodent problem will continue to persist. Our online platform, Wiley Online Library (wileyonlinelibrary.com) is one of the worlds most extensive multidisciplinary collections of online resources, covering life, health, social and physical sciences, and humanities. The additional attenuation of sound waves by air-dissipation resulted in an additional decline of 0.3, 1.3, and 2.5dB/m, respectively, for 1214, 2528, and 3541kHz, respectively. Groh, D.,
Effects of frequency compression and frequency transposition on fricative and affricate perception in listeners with normal hearing and mild to moderate hearing loss. On average, a relatively short exposure to the sound produced by a repellent device did not lead to significant adverse effects. Martin, N., and
If you need an account, pleaseregister here, The Journal of the Acoustical Society of America. (2013). document.getElementById( "ak_js_2" ).setAttribute( "value", ( new Date() ).getTime() ); 2803 Capitol Drive, Suite 3 Lee, J.,
Sim, C. S. (2017). , Reference hearing thresholds in an extended frequency range as a function of age, 32. DG5/PB_PP/IVC/13026). The protocol consisted of three parts: pre-exposure, exposure, and post exposure. Lovrinic, J. H. (1984). Ascone L, Kling C, Wieczorek J, Koch C, Khn S. Sci Rep. 2021 Mar 12;11(1):5814. doi: 10.1038/s41598-021-83527-z. Sung, J. H.,
Phone: (920) 731-2640. In order to determine absolute SPLs and signal spectra (linear and in 1/3 octave-bands between 20 and 46000Hz), the following equipment was used: A calibrated condenser 1/8 in. Yet, when the signal was perceived, as it was frequently for the younger population at the two lower frequencies settings (12-14 kHz, 25-25 kHz) and with 2 sources emitting, it was considered to be disturbing by several participants. Trinidad, A.,
https://doi.org/10.1016/j.ultras.2014.04.008, Assessment of short-term exposure to an ultrasonic rodent repellent device. Aflitto, N., and
As mentioned above, due to the increasing geometrical expansion of the wave front with increasing distance from the source, the SPL decreased with increasing distance. Grzesik, J., and
Abel, R.,
In the second approach, which was done to verify the values of the first one, the SPL was determined at 1m from the source to obtain a better signal-to-noise ratio (the noise being mainly of electronic nature). In the case of a concrete floor, the reflection coefficient approaches 100%. , Howard, C. Q.,
Potential adverse effects were evaluated perceptually with 25 young and 25 middle-aged persons, all with normal hearing thresholds, in a quiet room using different outcome measures, including a 15-item survey presented before and immediately after each condition. Since the rotation of the dial was continuous, its position is subject to frequency variations, typically in the order of 1kHz compared to the values listed in the specifications sheet. Janssen, S., and
Maso, S.,
A setup was built in which broadband sound (550kHz) was generated by a homemade spark source, reaching the microphone directly and via reflection off a slab of soil covered by grass. , How pleasant sounds promote and annoying sounds impede health: A cognitive approach, 10. Kei, J.,
Part 5Reference equivalent threshold sound pressure levels for pure tones in the frequency range 8 kHz to 16 kHz, Absorption of sound in air versus humidity and temperature, Exposure limits for airborne sound of very high frequency and ultrasonic frequency, AcousticsStatistical distribution of hearing thresholds as a function of age, 5. It is advised to use these devices in key areas where you have seen a mouse or other rodent, or where you have seen signs of one (droppings, track marks, etc.). Federal government websites often end in .gov or .mil. , Rodriguez Valiente, A.,
These could be selected remotely by means of an electronically controlled switch with three positions. Pienkowski, M.,
Takahashi, H. (2014b). Even though ultrasonic rodent repellents ultimately dont prevent rodents, prevention is key to eliminating rodents in your home. Are some people suffering as a result of increasing mass exposure of the public to ultrasound in air? Moore, B. C. (2014). Hansen, C. H., and
Jouvent, R., and
Dauman, N.,
Collet, L. (2002). Fifteen items of the survey (experiment 2). This sound was audible to several listeners, especially the younger ones. Exposure tests were performed in a larger semi-anechoic room, which was better adapted to host people comfortably. For the objective characterization of exposure conditions evaluated perceptually in experiment 2, the Kemo device and the L020 loudspeaker were placed at 6.5m from the measurement-device and about 3.8m apart from each other. Carson, M. B. Keiner, A. J.,
Accessibility Alexander JM, Kopun JG, Stelmachowicz PG. These properties were audible when listening to recordings played at a lower sampling frequency. An indicator on the dial pointed to a scale from 0 to 10. (2016). Cacace, A. T.,
Andersson, L., and
Kei, J.,
, A review of hyperacusis and future directions: Part I. Definitions and manifestations, 31. , Beahan, N.,
Sung, J. H.,
(2006). Charles, B., and
Garcia Berrocal, J. R.,
Second, a perceptual evaluation of the different sound conditions was carried out in young and middle-aged persons, all with normal hearing thresholds between 125Hz and 8kHz (experiment 2). Pienkowski, M.,
Pure tone thresholds were only determined before exposure, mainly because the step size/error of the audiometer is on the order of 5dB. In this room the average background SPL was 21.5 dBA. Effects of dynamic-range compression on the spatial attributes of sounds in normal-hearing listeners. 
Khan, A. uta, D., and
In a reverberant space, this can lead to substantial enhancement of the SPL(s). Under laboratory conditions, a continuous sound at less than 120 db (decibels) at any given frequency from 4-19 kc (kilocycles per second) was ineffective in deterring wild and laboratory rats (Rattus norvegicus) from entering and foraging in interconnected boxes (6 6 5 ft). Comment on Are some people suffering as a result of increasing mass exposure of the public to ultrasound in air?,, 1. 2021 Jun 15;18(12):6463. doi: 10.3390/ijerph18126463. Roncancio, E. R.,
The .gov means its official. Level differences between different device settings were due to the increasing attenuation at higher frequencies, which is substantial at 6.5m. In addition to the distance between the source and the person, sound levels depend on the orientation of the device and of the test person's head, and on the contribution of the reflection by concrete surface or soil covered by grass to the total SPL. However, for the investigated device, it did show that the emitted signal contains certain components that are audible to young adults and middle-aged persons, and although children were not tested in this study, a logical deduction from the published hearing threshold for children would suggest the possibility that the measured audible emissions could be too loud and annoying for prolonged continuous exposure in children and/or persons who are susceptible to noise.
Martin, N., and
Hooiveld, M., and
, Decreased sound tolerance: Hyperacusis, misophonia, diplacousis, and polyacousis, 21. , Chopra, A.,
Settings lower than 5 were not included, as their respective frequencies were clearly in the audible range, and expected to be perceived as even more disturbing than the tested ones, especially with two sources on (or with one source at a shorter distance from the subject). Given the increasing usage of ultrasonic devices as well as the much longer exposure of high frequency and ultrasound in domestic usage, careful consideration and better guidelines are required, especially for those who are most sensitive to sound. Collet, L. (2002). Selecting this option will search all publications across the Scitation platform, Selecting this option will search all publications for the Publisher/Society in context, Exposure to wind turbine noise: Perceptual responses and reported health effects, Long-term effects of noise reduction measures on noise annoyance and sleep disturbance: The Norwegian facade insulation study, Assessment of noise measurements made with a continuous monitoring in time, Short-term annoyance reactions to stationary and time-varying wind turbine and road traffic noise: A laboratory study, Long-term road traffic noise exposure is associated with an increase in morning tiredness, Audio-visual interaction and perceptual assessment of water features used over road traffic noise, Exposure-response relationships for annoyance due to freight and passenger railway vibration exposure in residential environments, A procedure for the assessment of low frequency noise complaints, Effects of very high-frequency sound and ultrasound on humans. For this reason, ultrasonic rodent repellents are highly appealing to homeowners for the proclaimed ability to repel rodents from overstaying their welcome. Davis, A.,
2021 Nov 8;8:760845. doi: 10.3389/fvets.2021.760845. II. Groh, D.,
Takahashi, H. (2014b). Jilek, M.,
Dolder CN, Fletcher MD, Lloyd Jones S, Lineton B, Dennison SR, Symmonds M, White PR, Leighton TG. Bartolucci, G. B. Brink, M.,
Scapellato, M. L.,
Lee J, Dhar S, Abel R, Banakis R, Grolley E, Lee J, Zecker S, Siegel J. , Changes in otoacoustic emissions and high-frequency hearing thresholds in children and adolescents, 15. , Jilek, M.,
Founded in 1807, John Wiley & Sons, Inc. has been a valued source of information and understanding for more than 200 years, helping people around the world meet their needs and fulfill their aspirations. Basner, M.,
Data were analyzed anonymously. Subsequently, the subject responded to items 415 on a Likert scale. High-Frequency Audiometry in Women with and without Exposure to Workplace Noise. Keiner, A. J.,
van Kamp, I.,
If your rodent problem continues to persist, call in an expert. Ota, A., and
Dauman, N.,
For terms and use, please refer to our Terms and Conditions Banakis, R.,
With settings 8 and 9, however, the presence of the 45kHz signal component that accompanied the ultrasonic 2528kHz signal, was found disturbing by several persons. Lanser, J. J. , Lee, J.,
PMC For instance, we are aware of clinical significant hyperacusis occurring in approximately 1.75% of the general population (, Children form another important demographic subset within the population. , Dahl, T.,
, Auditory and non-auditory effects of noise on health, 34. Carrieri, M.,
, Andringa, T. C., and
Heres the breakdown. Tyler, R. S.,
Dauman, N.,
Give us a call or contact us online for an inspection and plan of action. , Bio-effects and safety of low-intensity, low frequency ultrasonic exposure, 33. The spark source and microphone were placed at about 13cm above the soil covered by grass and about 30cm from each other. Bang, H. J.,
To the mouse, the frequencies will sound like a loud jackhammer. Ultrasonic rodent repellents are small devices that emit high-frequency sound waves that are claimed intolerable to rodents. Chung, S.,
MeSH Mohan, K., and
(2012). Trevisan, A., and
With a growing open access offering, Wiley is committed to the widest possible dissemination of and access to the content we publish and supports all sustainable models of access. Wiley has published the works of more than 450 Nobel laureates in all categories: Literature, Economics, Physiology or Medicine, Physics, Chemistry, and Peace. Mohan, K., and
, Investigation on high-frequency noise in public space, 37. Selecting this option will search the current publication in context. . Baliatsas, C.,
, Tyler, R. S.,
Andersson, G.,
Here are a few reliable prevention methods: Contact Wil-Kil for Effective Rodent Control. Kabelka, Z., and
The addition of the external loudspeaker resulted in an increase of 3dB (Table, Hearing thresholds were determined separately of the left and right ear for frequencies between 1 and 16 kHz to ensure normal hearing. and transmitted securely. Acton, W. I., and
Pre-exposure: Thresholds for high frequency sinusoids were obtained before commencing the perceptual experiment, and participants responded to items 414 of the survey in order to have a baseline. (1967). official website and that any information you provide is encrypted Grigg EK, Chou J, Parker E, Gatesy-Davis A, Clarkson ST, Hart LA. Items 1 and 2 were scored as yes/no and only administered once, prior to commencing exposure. Maso, S.,
Suitable topics include the results and interpretations of investigations into the biology and ecology of wildlife that can be used for management. In order to assess the effect of reflections in a garden setting, we also determined the high frequency sound reflection coefficient of soil covered by grass. Syka, J. Wiley is a global provider of content and content-enabled workflow solutions in areas of scientific, technical, medical, and scholarly research; professional development; and education. B&K 4231 1kHz, 94dB SPL calibrator for reference calibration. Some homeowners have noted an immediate effect at first, but over time the rodent problem will continue to persist. Our online platform, Wiley Online Library (wileyonlinelibrary.com) is one of the worlds most extensive multidisciplinary collections of online resources, covering life, health, social and physical sciences, and humanities. The additional attenuation of sound waves by air-dissipation resulted in an additional decline of 0.3, 1.3, and 2.5dB/m, respectively, for 1214, 2528, and 3541kHz, respectively. Groh, D.,
Effects of frequency compression and frequency transposition on fricative and affricate perception in listeners with normal hearing and mild to moderate hearing loss. On average, a relatively short exposure to the sound produced by a repellent device did not lead to significant adverse effects. Martin, N., and
If you need an account, pleaseregister here, The Journal of the Acoustical Society of America. (2013). document.getElementById( "ak_js_2" ).setAttribute( "value", ( new Date() ).getTime() ); 2803 Capitol Drive, Suite 3 Lee, J.,
Sim, C. S. (2017). , Reference hearing thresholds in an extended frequency range as a function of age, 32. DG5/PB_PP/IVC/13026). The protocol consisted of three parts: pre-exposure, exposure, and post exposure. Lovrinic, J. H. (1984). Ascone L, Kling C, Wieczorek J, Koch C, Khn S. Sci Rep. 2021 Mar 12;11(1):5814. doi: 10.1038/s41598-021-83527-z. Sung, J. H.,
Phone: (920) 731-2640. In order to determine absolute SPLs and signal spectra (linear and in 1/3 octave-bands between 20 and 46000Hz), the following equipment was used: A calibrated condenser 1/8 in. Yet, when the signal was perceived, as it was frequently for the younger population at the two lower frequencies settings (12-14 kHz, 25-25 kHz) and with 2 sources emitting, it was considered to be disturbing by several participants. Trinidad, A.,
https://doi.org/10.1016/j.ultras.2014.04.008, Assessment of short-term exposure to an ultrasonic rodent repellent device. Aflitto, N., and
As mentioned above, due to the increasing geometrical expansion of the wave front with increasing distance from the source, the SPL decreased with increasing distance. Grzesik, J., and
Abel, R.,
In the second approach, which was done to verify the values of the first one, the SPL was determined at 1m from the source to obtain a better signal-to-noise ratio (the noise being mainly of electronic nature). In the case of a concrete floor, the reflection coefficient approaches 100%. , Howard, C. Q.,
Potential adverse effects were evaluated perceptually with 25 young and 25 middle-aged persons, all with normal hearing thresholds, in a quiet room using different outcome measures, including a 15-item survey presented before and immediately after each condition. Since the rotation of the dial was continuous, its position is subject to frequency variations, typically in the order of 1kHz compared to the values listed in the specifications sheet. Janssen, S., and
Maso, S.,
A setup was built in which broadband sound (550kHz) was generated by a homemade spark source, reaching the microphone directly and via reflection off a slab of soil covered by grass. , How pleasant sounds promote and annoying sounds impede health: A cognitive approach, 10. Kei, J.,
Part 5Reference equivalent threshold sound pressure levels for pure tones in the frequency range 8 kHz to 16 kHz, Absorption of sound in air versus humidity and temperature, Exposure limits for airborne sound of very high frequency and ultrasonic frequency, AcousticsStatistical distribution of hearing thresholds as a function of age, 5. It is advised to use these devices in key areas where you have seen a mouse or other rodent, or where you have seen signs of one (droppings, track marks, etc.). Federal government websites often end in .gov or .mil. , Rodriguez Valiente, A.,
These could be selected remotely by means of an electronically controlled switch with three positions. Pienkowski, M.,
Takahashi, H. (2014b). Even though ultrasonic rodent repellents ultimately dont prevent rodents, prevention is key to eliminating rodents in your home. Are some people suffering as a result of increasing mass exposure of the public to ultrasound in air? Moore, B. C. (2014). Hansen, C. H., and
Jouvent, R., and
Dauman, N.,
Collet, L. (2002). Fifteen items of the survey (experiment 2). This sound was audible to several listeners, especially the younger ones. Exposure tests were performed in a larger semi-anechoic room, which was better adapted to host people comfortably. For the objective characterization of exposure conditions evaluated perceptually in experiment 2, the Kemo device and the L020 loudspeaker were placed at 6.5m from the measurement-device and about 3.8m apart from each other. Carson, M. B. Keiner, A. J.,
Accessibility Alexander JM, Kopun JG, Stelmachowicz PG. These properties were audible when listening to recordings played at a lower sampling frequency. An indicator on the dial pointed to a scale from 0 to 10. (2016). Cacace, A. T.,
Andersson, L., and
Kei, J.,
, A review of hyperacusis and future directions: Part I. Definitions and manifestations, 31. , Beahan, N.,
Sung, J. H.,
(2006). Charles, B., and
Garcia Berrocal, J. R.,
Second, a perceptual evaluation of the different sound conditions was carried out in young and middle-aged persons, all with normal hearing thresholds between 125Hz and 8kHz (experiment 2). Pienkowski, M.,
Pure tone thresholds were only determined before exposure, mainly because the step size/error of the audiometer is on the order of 5dB. In this room the average background SPL was 21.5 dBA. Effects of dynamic-range compression on the spatial attributes of sounds in normal-hearing listeners. Khan, A. uta, D., and
In a reverberant space, this can lead to substantial enhancement of the SPL(s). Under laboratory conditions, a continuous sound at less than 120 db (decibels) at any given frequency from 4-19 kc (kilocycles per second) was ineffective in deterring wild and laboratory rats (Rattus norvegicus) from entering and foraging in interconnected boxes (6 6 5 ft). Comment on Are some people suffering as a result of increasing mass exposure of the public to ultrasound in air?,, 1. 2021 Jun 15;18(12):6463. doi: 10.3390/ijerph18126463. Roncancio, E. R.,
The .gov means its official. Level differences between different device settings were due to the increasing attenuation at higher frequencies, which is substantial at 6.5m. In addition to the distance between the source and the person, sound levels depend on the orientation of the device and of the test person's head, and on the contribution of the reflection by concrete surface or soil covered by grass to the total SPL. However, for the investigated device, it did show that the emitted signal contains certain components that are audible to young adults and middle-aged persons, and although children were not tested in this study, a logical deduction from the published hearing threshold for children would suggest the possibility that the measured audible emissions could be too loud and annoying for prolonged continuous exposure in children and/or persons who are susceptible to noise.