It has been inspected in terms of acoustical effects, Noise Isolation Class (NIC), and Noise Reduction Coefficient (NRC).
A na-enyocha ya na usoro nke nsonaazụ acoustical, ụzụ dị iche iche (nic), na ọnụ ọgụgụ mkpọtụ mkpọtụ (NRC)..