What is LA90?

Answer 1

LA90 is a standard way of specifying background noise over a given time. It is the noise level that is exceeded for 90% of the time being considered. E.g. 25dBA LA90 (10min) means that for a given 15 min period noise levels would be above 25dBA for 90% of the time. It can also be used as a Noise Management Level for construction purposes where works are being conducted around residential areas.

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