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Noise and vibration
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2023
Andrew Colthurst, Steve Fisher
SEL – The Sound Exposure Level (SEL) index, also sometimes referred to as the Single Event Level, and denoted LAE (in dB), may be used to represent the sound energy of a discrete event, for example a train passing by. Using the SEL, which is the equivalent continuous sound level, Leq,T expressed as a 1-second Leq, the equivalent continuous A-weighted sound pressure level can be calculated for a series of events over a given time period as follows: Statistical parameters – By rapid sampling of the noise level over the measurement period the statistical noise level exceeded for N per cent of the total measurement time T, where N is a percentage between 1 and 100, can be calculated. For example, the LA10,T can be considered to be the ‘average maximum’ sound level and in the UK is used to describe road traffic noise. Commonly the LA90,T is described as representing the ‘background sound level’. The LA50,T is the arithmetic average of the instantaneous sound levels measured during the period T.
Environmental impacts and mitigation
Published in Lucy Budd, Stephen Ison, Air Transport Management, 2020
One of the challenges associated with aircraft noise is the number of different methodological techniques and metrics that can be used to quantify it (Example 18.2). The simplest measure of a noise event, such as an aircraft flying overhead, is the maximum sound level that occurred during the event. This is measured in dB(A) (the highest noise level), where the greater the value, the greater the risk of disturbance. The sound exposure level (SEL) of a noise event is the sound level in dB(A) that would be recorded if the energy of the entire event was compressed into a constant sound level lasting one second. However, measuring individual aircraft noise events in this way does not assess the full impact of the noise exposure, as it does not take account of the combined impact of many aircraft over longer periods of time or the effects of noise at anti-social times of the day.
Fundamentals of human response to sound
Published in Frank Fahy, John Walker, Fundamentals of Noise and Vibration, 2003
The Sound Exposure Level (SEL), (the acronym is sometimes more easily remembered as the Single Event Level), is a specific measure applicable to separately identifiable noise events. Obviously, the maximum F time weighted level (known as LAmax) of an event cannot convey any impression of the duration or relative frequency content of the sound. SEL is effectively a measure of the total acoustic energy in the event sealed back to a standard duration of I s and is calculated in the same way as LAeq except that the integrated A-wcightcd sound pressure squared signal is not divided by the measurement duration.
Effective analysis of noise levels due to vehicular traffic in urban area using deep learning with OALO model
Published in International Journal of Computers and Applications, 2022
The measurements have been duly made with the Sound Level Meter (SLM) 100, which incessantly exhibits the Sound Pressure Level (SPL), Equivalent sound level (Leq), Maximum and Minimum sound pressure level and the Sound Exposure Level (SEL) integrated over the specified time of operation. The appropriate recordings of A-weighted sound-pressure levels were carried out during the interval of one minute in the morning, afternoon and the evening between 8 am and 9 pm The SLM was positioned 15 m away from the focal point of the carriageway and mounted at a height of 1.2 m from the ground. The location of the civil hospital, Nasik city and its vehicular traffic are beautifully depicted in Figure 1.
Mathematical optimization in enhancing the sustainability of aircraft trajectory: A review
Published in International Journal of Sustainable Transportation, 2020
Ahmed W.A. Hammad, David Rey, Amani Bu-Qammaz, Hanna Grzybowska, Ali Akbarnezhad
For aircraft noise impact assessment due to flight paths, the integrated noise model (INM), developed by the Federal Aviation Administration (FAA) (Salah, 2014), was adopted until recently, where it has now been replaced by the “Aviation Environmental Design Tool” (AEDT) (Federal Aviation Administration, 2015). The AEDT process for determining the sound exposure level at a specific location from an aircraft or airport, relies on the use of the Impact Set Graphs that account for the distances from aircraft to observer (Federal Aviation Administration, 2015).