Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ear Protective Devices”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources
PubMed2004

Development of a new standard laboratory protocol for estimation of the field attenuation of hearing protection devices: sample size necessary to provide acceptable reproducibility.

The mandate of ASA Working Group S12/WG11 has been to develop "laboratory and/or field procedure(s) that yield useful estimates of field performance" of hearing protection devices (HPDs). A real-ear attenuation at threshold procedure was selected, devised, tested for one earmuff and three earplugs via an interlaboratory study involving five laboratories and 147 subjects, and incorporated into a new standard that was approved in 1997 [Royster et al., "Development of a new standard laboratory protocol for estimating the field attenuation of hearing protection devices. Part I. Research of Working Group 11, Accredited Standards Committee S 12, Noise," J. Acoust. Soc. Am. 99, 1506-1526; ANSI, S12.6-1997, "American National Standard method for measuring real-ear attenuation of hearing protectors" (American National Standards Institute, New York, 1997)]. The subject-fit methodology of ANSI S12.6-1997 relies upon listeners who are audiometrically proficient, but inexperienced in the use of HPDs. Whenever a new method is adopted, it is important to know the effects of variability on the power of the measurements. In evaluation of protector noise reduction determined by experimenter-fit, informed-user-fit, and subject-fit methods, interlaboratory reproducibility was found to be best for the subject-fit method. Formulas were derived for determining the minimum detectable difference between attenuation measurements and for determining the number of subjects necessary to achieve a selected level of precision. For a precision of 6 dB, the study found that the minimum number of subjects was 4 for the Bilsom UF-1 earmuff, 10 for the E.A.R Classic earplug, 31 for the Willson EP100 earplug, and 22 for the PlasMed V-51R earplug.

Auditory Threshold↗
PubMed1983

Influence of physiological noise and the occlusion effect on the measurement of real-ear attenuation at threshold.

The most commonly alleged experimental artifact associated with real-ear attenuation at threshold (REAT) measurements of hearing protection devices (HPDs) was examined: Masking of the protected thresholds due to physiological noise amplified by the occlusion effect. An ear canal mounted subminiature microphone was used to obtain objective measures of physiological noise in occluded and unoccluded test conditions and of the insertion loss (IL) of insert, semi-aural, supra-aural and circumaural HPDs when exposed to broadband noise with a sound pressure level of 93 dB. Measurements spanned 1/3 octave bands from 125 Hz to 2 kHz. Attenuation was also measured via a subjective REAT procedure and the magnitude of the occlusion effect was examined via bone conduction audiometry. The IL data confirmed the accuracy of the REAT results except at the lowest frequencies tested, where the degree to which the REAT values were spuriously inflated was quantified and found to be device related. Furthermore, the magnitude of the error (which never exceeded 5 dB) could be predicted by measuring the physiological noise in the occluded ear and calculating how much this would mask the occluded threshold. It was noted that no evidence was found in the data to suggest a dependency of HPD attenuation on sound level.

Adult↗
PubMed2001

Isolating the auditory system from acoustic noise during functional magnetic resonance imaging: examination of noise conduction through the ear canal, head, and body.

Approaches were examined for reducing acoustic noise levels heard by subjects during functional magnetic resonance imaging (fMRI), a technique for localizing brain activation in humans. Specifically, it was examined whether a device for isolating the head and ear canal from sound (a "helmet") could add to the isolation provided by conventional hearing protection devices (i.e., earmuffs and earplugs). Both subjective attenuation (the difference in hearing threshold with versus without isolation devices in place) and objective attenuation (difference in ear-canal sound pressure) were measured. In the frequency range of the most intense fMRI noise (1-1.4 kHz), a helmet, earmuffs, and earplugs used together attenuated perceived sound by 55-63 dB, whereas the attenuation provided by the conventional devices alone was substantially less: 30-37 dB for earmuffs, 25-28 dB for earplugs, and 39-41 dB for earmuffs and earplugs used together. The data enabled the clarification of the relative importance of ear canal, head, and body conduction routes to the cochlea under different conditions: At low frequencies (< or =500 Hz), the ear canal was the dominant route of sound conduction to the cochlea for all of the device combinations considered. At higher frequencies (>500 Hz), the ear canal was the dominant route when either earmuffs or earplugs were worn. However, the dominant route of sound conduction was through the head when both earmuffs and earplugs were worn, through both ear canal and body when a helmet and earmuffs were worn, and through the body when a helmet, earmuffs, and earplugs were worn. It is estimated that a helmet, earmuffs, and earplugs together will reduce the most intense fMRI noise levels experienced by a subject to 60-65 dB SPL. Even greater reductions in noise should be achievable by isolating the body from the surrounding noise field.

Adult↗
PubMed1991

Signal detection and speech perception with level-dependent hearing protectors.

An experiment was conducted to investigate signal detection and speech perception with level-dependent hearing protectors. Twenty normal-hearing young adults participated in the first phase of this program, the ultimate objective of which was an assessment of the effect of hearing loss. For each subject, measurements were made of the detection of one-third octave noise bands centered at 500, 1000, 2000 and 4000 Hz, consonant discrimination, and word recognition. Performance on these tests was evaluated in quiet and in a background of 75 dB SPL cable swager noise, with the ears unoccluded and protected with four different muffs. The devices selected were the E-A-R 9000 and BILSOM 2390 and their conventional level-independent counterparts, the E-A-R 3000 and BILSOM 2315. The results indicated that signal detection in noise generally remained the same or was slightly enhanced when the protectors were worn. For consonant discrimination, there were no differences among the various protectors in quiet, while in noise the wearing of the BILSOM 2390 resulted in a significant decrement in the intelligibility of the initial consonant. For word recognition, the BILSOM 2390 resulted in an advantage in quiet, particularly for sentences with low contextual cues. The reverse effect was true in noise. The results obtained for the E-A-R 9000 were similar to those for the two conventional HPDs.

Acoustics↗
PubMed1999

A comprehensive noise survey of the S-70A-9 Black Hawk helicopter.

PURPOSE: This paper reports the results of a comprehensive noise survey of the Sikorsky S-70A-9 Black Hawk helicopter environment and provides an assessment of the hearing protection devices worn by Australian Army personnel exposed to that environment. METHODS AND RESULTS: At-ear noise levels were measured at 4 positions in the cabin of the Black Hawk under various flight conditions and at 13 positions outside the Black Hawk under various ground running conditions using the Head Acoustic Measurement System (Head, GmbH). The attenuation properties of the hearing protection devices (HPDs) normally worn by aircrew and maintenance crews (the ALPHA helmet and the Roanwell MX-2507 Communications headset) were also assessed. At-ear sound pressure levels that would be experienced by personnel wearing their normal HPDs were determined at the positions they would normally occupy in and around the aircraft. CONCLUSION: Results indicate that HPDs do not provide adequate hearing protection to meet current hearing conservation regulations which allow a permissible noise exposure of 85 dB(A) for an 8-h day.

Acoustics↗
PubMedDate not supplied

Efficacy of an intervention to promote use of hearing protection devices by firefighters.

Numerous cases of hearing loss consistent with noise-induced damage were noted among firefighters in the city of Columbia, MO. A survey of firefighting vehicles in operation showed that the firefighters were exposed to excessive noise levels and put at risk for noise-induced hearing loss (NIHL). Audiologic evaluation showed that 36 percent of the firefighters had moderate or severe hearing loss (a threshold of 40 decibels (dB) or more at 3,000, 4,000, or 6,000 hertz (Hz) in either ear). An educational program on NIHL was then carried out to increase the use of hearing protection devices (HPDs) by firefighters, followed by an evaluation of the intervention. The educational intervention successfully increased knowledge of NIHL, positive attitudes toward HPDs, and resulted in more frequent use of HPDs. After the intervention, 85 percent of firefighters regularly used HPDs compared with 20 percent before the intervention. Recommendations are made for fire departments to reduce the risk of NIHL.

Audiometry↗
PubMed1989

Auricular injury and the use of headgear in wrestlers.

Questionnaires designed to assess attitudes and use of headgear were completed by 537 Division I collegiate wrestlers. Only 35.2% of the wrestlers wore headgear all of the time during practice as opposed to 92.4% during competition, which was a statistically significant difference. The most common reason for not wearing headgear was discomfort (35%). There were 482 participating in nonschool team events, and 203 (42%) described headgear use as "seldom or never." However, there was a statistically significant difference of developing auricular hematoma while wearing headgear (26%) vs not wearing headgear (52%). There were 208 (39%) who reported a permanent auricular deformity resulting from an injury that occurred with (10.6%) or without (26.6%) headgear. These results suggest that headgear provides only partial protection and that nonuse is widespread, causing a surprisingly high frequency of permanent auricular deformities.

Adolescent↗
PubMed1991

Air bag ear.

Explore the source record for details and available documents.

Accidents, Traffic↗
PubMedDate not supplied

Compications in acoustic neuroma surgery.

The findings in a series of 80 cerebellopontine angle tumors are presented. Complications and results are covered in detail. A new method of controlling postoperative cerebrospinal fluid (CSF) leak is presented. Care of the eye in postoperative facial paralysis is emphasized, and a new type of moisture chamber is introduced.

Brain Edema↗
PubMed1984

Othematoma associated with ill-fitting helmet and high G load: a case report.

One case of othematoma caused by high +Gz load and an improperly fitted helmet is described. Many recommended modalities of treatment are followed by the reaccumulation of the fluid. Compression sutures should, therefore, be the treatment of choice. A properly-fitted, light-weight helmet can help prevent this injury.

Acceleration↗
PubMed1988

Usage of personal protective devices among Egyptian industrial workers.

A systematic random sample of 405 workers from metal, asbestos cement pipes, textile, and viscose rayon industries were interviewed using a prepared and tested questionnaire. Personal Protective Devices (PPDs), namely goggles, gloves, respirators, and ear defenders, had been distributed to all workers on the payroll and were used by 31.4%. Usage of PPDs was associated with the educational level, duration of occupation, awareness of the work hazards, and knowledge about the purpose of PPDs. Marked association was found between nonusage of PPDs and discomfort, interference with job performance, and the psychological feeling of lowering the person's prestige by the wearing of PPDs. Nonusage was also associated with lack of maintenance of the device and absence of supervision of its usage. Users were more numerous among married workers and workers with urban residence than among unmarried workers and those with rural residence, respectively. No association could be found between the rate of usage and the worker's age except for ear plugs, for which nonusage was proportional to the worker's age. The most important factors were those related to the role of the safety staff and the discomfort of the devices. Recommendations for occupational health authorities on the basis of the above evaluation are suggested.

Cooperative Behavior↗
PubMed1994

[Communication and noise. Speech intelligibility of airplane pilots with and without active noise compensation].

Noise exposure measurements were performed with pilots of the German Federal Navy during flight situations. The ambient noise levels during regular flight were maintained at levels above a 90 dB A-weighted level. This noise intensity requires wearing ear protection to avoid sound-induced hearing loss. To be able to understand radio communication (ATC) in spite of a noisy environment, headphone volume must be raised above the noise of the engines. The use of ear plugs in addition to the headsets and flight helmets is only of limited value because personal ear protection affects the intelligibility of ATC. Whereas speech intelligibility of pilots with normal hearing is affected to only a smaller degree, pilots with pre-existing high-frequency hearing losses show substantial impairments of speech intelligibility that vary in proportion to the hearing deficit present. Communication abilities can be reduced drastically, which in turn can affect air traffic security. The development of active noise compensation devices (ANC) that make use of the "anti-noise" principle may be a solution to this dilemma. To evaluate the effectiveness of an ANC-system and its influence on speech intelligibility, speech audiometry was performed with a German standardized test during simulated flight conditions with helicopter pilots. Results demonstrate the helpful effect on speech understanding especially for pilots with noise-induced hearing losses. This may help to avoid pre-retirement professional disability.

Adult↗
PubMed2004

An innovative, cost-effective, pressure-relieving device for burned ears.

Cosmetic disfigurement is a common result of facial burn injuries. Next to judicious wound care and timely wound closure, the application of pressure to maturing facial scars is a key factor in minimizing disfigurement. This is not true for ear burns, where pressure is contraindicated at all phases of recovery, thus making it mandatory to provide pressure-relief over the ears throughout rehabilitation. Though such a need has been understood since long ago, the availability of such a device is very rare in any developing nation. Moreover the cost of such splints is too expensive. This report presents an innovative idea to protect the ear with a low-cost splinting technique.

Burns↗