There are three types of Noise pollution monitoring: 1) Spot Reading or basic noise level monitoring – in this method single reading is taken using handheld device 2) Continuous Noise level Measurements – In this method noise level meter is kept on tripod for set duration and it takes reading after every set period. This helps us to understand trends and anomalies in noises 3) Longer term Noise level monitoring – In this method, noise levels are monitored for longer period such as few months to several years by small intervals such as 5 mins, 15 mins, 30mins or 1 hour or more. This helps us to understand noise pollution patterns over longer period.