ABSORPTION

Sound Absorption is a technique wherein various absorbent materials are strategically used to absorb sound to avoid unwanted reflected sound waves within a room or space. The main reason to use this technique is to reduce reverberation time (RT) for making the speech clearer. There are two rating methods prominently used across the world.

(a) NRC (Noise Reduction Coefficient): The term is majorly used within United State and defined as part of American Standards. The rating is unitless and it is a coefficient and the ranges are from 0 to 1. Higher the average NRC is the better will be the absorption property of the product.

(b) Weighted Absorption Coefficient: It is prominently used across the world and defined as part of ISO Standards. Similar to NRC, the rating is unitless and the ranges from 0 to 1.