What is a acceptable noise level??
Answers
Answer:
In general, sounds above 85 are harmful, depending on how long and how often you are exposed to them and whether you wear hearing protection, such as earplugs or earmuffs. Following is a table of the decibel level of a number of sounds. Noise levels. Noise. Average decibels (dB)
Answer:
In the ANL test, the listener first will adjust speech to a comfortable listening level. It is an adaptive procedure, so first they will adjust the speech so it is too loud, then too quiet, then to their most comfortable listening level.
Background noise will be added and the person is asked to adjust the level of the noise using a bracketing procedure, first to a level that is higher than they would like, then soft enough that they could easily understand the speech, and then to the highest level that they are willing to put up with while listening to the speech.
The difference between the speech level and the noise level is the person’s ANL.
You can think of it as a tolerated signal-to-noise ratio (SNR). The ANL equals the most comfortable speech level minus the highest tolerated noise level.
Explanation:
ANL is a procedure used to quantify listeners' willingness to listen to speech in the presence of background noise.
ANLs can be obtained in approximately 2-3 minutes and are reliable and consistent over time in both listeners with normal and impaired hearing.
ANLs are not related to speech perception in noise scores and do not change with the introduction of hearing aids, indicating that ANLs can be measured before hearing aids are fitted and used as a predictor of hearing aid use
. Most importantly, ANLs are related to a pattern of hearing aid use and can predict success with hearing aids with 85% accuracy.
Additionally, ANLs are thought to be mediated beyond the level of the periphery at the level of the central auditory nervous system in listeners with normal hearing.
Lastly, research has shown that ANLs can be improved through the use of pharmacological intervention in listeners with normal hearing and through the use of directional microphones and noise reduction algorithms in hearing aids for users of amplification.
Readers who are interested in additional information on ANL should look for an upcoming live e-Seminar on Audiology Online in March of 2007.
This event will be recorded and available through Audiology Online after the live presentation date.