Search results
Results From The WOW.Com Content Network
Higher ambient noise levels also cause animals to vocalize more loudly, which is called the Lombard effect. Researchers have found that humpback whales' song lengths were longer when low-frequency sonar was active nearby. [82] Underwater noise pollution is not only limited to oceans, and can occur in freshwater environments as well.
The lifestyle publication for seniors, Retirement Living, ranked 99 of the most populated U.S. cities based on their noise pollution level. Some of the factors taken into account when tabulating ...
The day-night average sound level (Ldn or DNL) is the average noise level over a 24-hour period. The noise level measurements between the hours of 22:00 and 07:00 are artificially increased by 10 dB before averaging. This noise is weighted to take into account the decrease in community background noise of 10 dB during this period.
When sound levels reach a high enough intensity, the sound, whether it is wanted or unwanted, may be damaging to hearing. [3] Environmental noise monitoring is the measurement of noise in an outdoor environment caused by transport (e.g. motor vehicles, aircraft, and trains), industry (e.g. machines) and recreational activities (e.g. music).
With regard to indoor noise pollution in residences, the U.S. Environmental Protection Agency (EPA) has not set any restrictions on limits to the level of noise. Rather, it has provided a list of recommended levels in its Model Community Noise Control Ordinance, which was published in 1975. For instance, the recommended noise level for indoor ...
strategic noise map shall mean a map designed for the global assessment of noise exposure in a given area due to different noise sources or for overall predictions for such an area." EU Member States are required to produce strategic noise maps in their main cities, near the main transport infrastructure and industrial sites. The main goals of ...
This noise abatement wall in The Netherlands has a transparent section at the driver's eye-level to reduce the visual impact for road users. Studies on noise barriers have shown mixed results on their ability to effectively reduce noise pollution. [11]
Sound level meters are commonly used in noise pollution studies for the quantification of different kinds of noise, especially for industrial, environmental, mining and aircraft noise. [2] [3] The current international standard that specifies sound level meter functionality and performances is the IEC 61672-1:2013. However, the reading from a ...