Long-term versus short-term noise monitoring: Strategies and implications in India

Abstract

The paper investigates the accuracy of short-term noise monitoring strategies w.r.t. the long-term noise monitoring. The difference in short-term strategies from the annual average representative values obtained from yearly noise monitoring data is quantified as error. Long-term continuous noise monitoring data in terms of monthly averages for 35 locations spread over 7 major cities of India is analyzed. The analysis shows that the error of _3 dBA from annual equivalent level is calculated with 95% probability for LDay (06-22 h) and LNight (22-06 h) value by adopting 1 month noise monitoring strategy. For higher accuracy, the random 2 months strategy is recommended, whereby an error of _2 dBA is achieved with a probability higher than 90%. The study reveals that short-term noise monitoring strategy followed gives a reliable accuracy levels w.r.t. continuous long-term monitoring and thus offers a best practicable and economical option (BPEO) for noise mapping of larger parts of the country.