In atmospheric sound transmission or noise pollution, ambient noise level is the sound pressure level at a given location, normally specified as a reference level to study a new intrusive sound source. Noise pollution (or environmental noise) is displeasing human- or machine-created sound that disrupts the activity or balance of human or animal life

Integrating Sound Level Meter

Ambient sound levels are often measured in order to map sound conditions over a spatial regime to understand their variation with locale. In this case the product of the investigation is a sound level contour map. A contour line (also Level set, isopleth, isoline, isogram or isarithm) of a function of two Alternatively ambient noise levels may be measured to provide a reference point for analyzing an intrusive sound to a given environment. For example, sometimes aircraft noise is studied by measuring ambient sound without presence of any overflights, and then studying the noise addition by measurement or computer simulation of overflight events. Aircraft noise is defined as Sound produced by any aircraft or its components during various phases of a flight on the ground while parked such as auxiliary power A computer simulation, a computer model or a computational model is a Computer program, or network of computers that attempts to simulate an Or roadway noise is measured as ambient sound, prior to introducing a hypothetical noise barrier intended to reduce that ambient noise level. Roadway noise is the collective sound energy emanating from Motor vehicles In the USA it contributes more to environmental noise exposure than any other noise source and is A noise barrier (also called a soundwall, sound berm, sound barrier, or acoustical barrier) is an exterior structure designed to protect

Ambient noise level is measured with a sound level meter. In Telecommunication, noise level is the Noise power, usually relative to a reference Sound level meters measure sound pressure level and are commonly used in Noise pollution studies for the quantification of almost any noise but especially for industrial It is usually measured in dB above a reference pressure level of 0. The decibel ( dB) is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power or intensity relative to 00002 Pa, i. e. , 20 μPa (micropascals) in SI units. A pascal is a newton per square meter. The centimeter-gram-second system of units, the reference level for measuring ambient noise level is 0. System (from Latin systēma, in turn from Greek systēma is a set of interacting or interdependent Entities, real or abstract 0002 dyn/cm². Most frequently ambient noise levels are measured using a frequency weighting filter, the most common being the A-weighting scale, such that resulting measurements are denoted dBA, or decibels on the A-weighting scale. A-weighting is the most commonly used of a family of curves defined in the International standard IEC616722003 and various national standards relating to the measurement of sound A-weighting is the most commonly used of a family of curves defined in the International standard IEC616722003 and various national standards relating to the measurement of sound

Ambient noise level is sometimes called background noise level, reference sound level or room noise level. In practical applications ambient noise levels are often reported using a day night weighting scheme such as Community noise equivalent level, (CNEL) in order to account for greater noise sensitivity in evening and nighttime hours.

See also

• A-weighting
• noise barrier
• Noise regulation
• Noise engineer
• Noise health effects
• Environmental noise

References