Unmasking the noise level in some lecture halls of Captain Elechi Amadi Polytechnic was carried out to determine the level of noise, its sources and effects on the students. With the use of technological tools like the sound level meter, noise level was measured in the morning, at noon, and in the evening. The selected study are lecture halls are the hall 1, A1, A2, TF1, GC3, A3, TF4 ICT Block, TF9, TF8, TF3, TF6, TF7, GC4, D2, B3, D1, B2 and GC2. The average sound level (dB) was calculated and recorded for each of the halls. It was found that the hall 1, occupied by the Public Administration students had the highest noise levels of 77.33 dB, followed by the Mass Communication Students in B3 with a noise level of 76dB. The Computer Science in TF4, Banking and Finance in GC3, Accountancy in TF1, Electrical and Electronics Technology in A2 and Science Laboratory Technology in ICT block had the noise level of 71.67dB, 69.67dB, 68.33dB, 68dB and 68dB respectively. Since the normal sound level is 65dBA, it then means that the halls which generate an average sound level above 65dBA, adequate fenestrations and ventilations should be provided, number of students in the lecture halls should be reduced, air conditions and fans should be installed and a steady power supply. Generally speaking, the polytechnic environmental noise level of 61.72dBA is less than the normal sound level.