China
Africa
Explore chapters and articles related to this topic
Answers
Published in Ken Addley, MCQs, MEQs and OSPEs in Occupational Medicine, 2023
Measurement of environmental noise level. It allows quick sound-level checks of machinery noise, office noise and other issues around the workplace to be carried out. It measures the instantaneous sound level with either A- or C-weighting. Most noise regulations require A-weighting. It also has both fast and slow time response. The device needs regular calibration, and depending on the device will have a range of 30 dB (A) to 130 dB (A) or 40 dB (C) to 130 dB (C). The unit of acoustic measurement for sound is usually the decibel (dB); however, some sound-level meter devices also determine the equivalent continuous sound level (Leq) and other acoustic parameters.
Noise or Sound Perception
Published in William C. Beck, Ralph H. Meyer, The Health Care Environment: The User’s Viewpoint, 2019
As pointed out earlier, the solution is not easy. It begins when responsible people recognize that the problem exists and determine to do something about it. They have several choices and what may work well in one environment may very well fail in another. Initially one must determine how serious the problem may be and this can easily be done by acquisition of a sound level meter capable of accurate “A” scale readings. There are several available for less than $500. Readings taken at various locations throughout the hospital at various times of the day and night will provide a perspective of the problem. It is well to remember that the infrequent sharp sounds are not of as great a concern as those of constant level. When the levels have been established the real problem begins—what to do about it. As was pointed out the solutions are not easy but the quickest, most thorough and effective device may be the one individual with the courage and authority to tell others “you are making too much noise, please be quiet”. But provide him with the meter because he too is subject to the environment and without the meter he may ultimately become a contributor to, rather than a controller of, sound.
Hearing Tests in Children
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
A wide range of sound stimuli can be used to elicit a response, including voice (e.g. unforced ‘S’ = high frequency, or hum = low frequency), musical toys, calibrated high-frequency rattle, NBN or warble tones. Pure tones should be avoided due to the potential creation of standing waves, resulting in unpredictable sound levels. Responses to any sound stimulus may be valid, provided the intensity and the frequency spectrum, as delivered at the level of the ear, can be established. A sound level meter should be employed to check the intensity of the stimulus by accurately reproducing the sound and the distance from the ear. Although it has been demonstrated that infants are more likely to respond to wide-band sounds, this will inevitably provide less information regarding frequency-specific hearing as required for diagnosis and possible amplification prescription. Sound generators delivering calibrated narrow-band and frequency-modulated warble tones have been demonstrated to be effective at eliciting a response and are therefore generally preferred.22
Development of the Turkish hearing in noise test for children
Published in Cochlear Implants International, 2023
Ecem Kartal Özcan, Şule Çekiç, Gonca Sennaroglu, Sigfrid D. Soli
All the participants were tested with the Turkish HINT-C in the double-wall audiometric test room (2.84 × 2.73 m2) of Industrial Acoustics Company Inc. (New York). HINT software, which is designed to provide adaptive or fixed-level Turkish HINT-C protocols with standard headphones (supra-aural or circumaural) or stereo sound field speakers, was used. JBL Control One (Harman International, Stamford, USA) speakers were used for evaluations. The loudspeakers were calibrated with the Wintact WT1357 (Shenzhen, China) sound level meter via HINT software. The adaptive test protocol (Nilsson et al., 1996) was used through the speakers under four test conditions: a quiet condition and three noise conditions defined according to the location of the noise source (Quiet, NF, NR, and NL). Speech stimuli were presented through speakers placed 90° apart and 1 m away from the center of the listener's head. The testing loudspeakers were calibrated by following the procedures in the HINT software and positioned at a 90° angle to each other. The listener was positioned to face the left speaker for the noise right condition (NR) and the right speaker for the noise left condition (NL).
Sound and light levels in intensive care units in a large urban hospital in the United States
Published in Chronobiology International, 2023
Michael J. Leone, Hassan S. Dashti, Brian Coughlin, Ryan A. Tesh, Syed A. Quadri, Abigail A. Bucklin, Noor Adra, Parimala Velpula Krishnamurthy, Elissa M. Ye, Aashritha Hemmige, Subapriya Rajan, Ezhil Panneerselvam, Jasmine Higgins, Muhammad Abubakar Ayub, Wolfgang Ganglberger, Luis Paixao, Timothy T. Houle, B. Taylor Thompson, Oluwaseun Johnson-Akeju, Richa Saxena, Eyal Kimchi, Sydney S. Cash, Robert J. Thomas, M. Brandon Westover
The core of the sound and light sensor is an Arduino Uno embedded computing system (Arduino.cc) with an Adafruit data logging shield for writing timestamped sensor measurements to.csv files on an SD card. For sound level measurements we used a Gravity Sound Level Meter with a measuring range of 30-130dBA, A-weighted frequency weighting, and a sampling rate of 3.33 Hz. Light levels were measured with an Adafruit TSL2561 digital luminosity sensor (Adafruit.com) and data were recorded as lux values. These sensors have a range of 0.1 to 40 000 lux and were set to medium gain for best performance in both bright and dim light conditions. Integration time was set to 100 ms to balance speed of sampling and resolution of lux sensor output. To protect the device, we designed a 3D-printed enclosure to hold the Arduino, SD shield, and both sensors. Ports for the sensor components as well as the SD card and power/USB ports on the Arduino allow for data collection without any need for disassembly. Details on the design and instructions to build the sensor are included in the Supplemental Material.
Impulse noise measurement in view of noise hazard assessment and use of hearing protectors
Published in International Journal of Occupational Safety and Ergonomics, 2023
Standard No. ISO 9612:2009 [14] for the determination of occupational noise exposure includes the requirement that the sound level meters used shall meet the requirements for IEC 61672-1 [15], class 1 or class 2 instrumentation. In accordance with the provisions of Directive 2003/10/EC [1], the measurement equipment used for the assessment of noise hazard should make it possible to measure the noise parameters taken into account in the assessment and determine whether, among others, the exposure limit values for these parameters have been exceeded. When measuring the parameters of impulse noise, it may happen that the sound pressure level characterizing this noise will exceed the dynamic range upper limit of the sound level meter. Table 1 presents examples of the limits of the possibilities of measuring noise parameters by type of approved sound level meters. These data, which are included in the sound level meter user manuals, include LCpeak, which, as a parameter related to the instantaneous value of the signal, is particularly applicable to characterize the properties of impulse noise. The upper limit of the measurement range is also determined for LAeq, which is also used in the assessment of noise hazard.