Breathing Sounds – Determination of Extremely Low SPL

School of Electrical Engineering, Universiti Teknologi Malaysia,  

^* Email: mokhtarharun@utm.my Phone: +6075535358

Abstract

Breathing sound is an extremely low SPL that results from inspiration and expiration process in the lung. Breathing sound can be used to diagnose persons with complications with breathing. Also, the sound can indicate the effectiveness of treatment of lung disease such as asthma. the purpose of this study was to identify SPL of breathing sounds, over six one octave center frequencies from 63 Hz to 4000 Hz, from the recorded breathing sounds in .wav files. Breathing sounds of twenty participants with normal weight BMI had been recorded in an audiometry room. the breathing sound was acquired in two states: at rest and after a 300 meters walk. Matlab had been used to process the breathing sounds that are in .wav files to come up with SPL (in dB). It has been found out that the SPL of breathing sound of all participants are positive at frequencies 63 Hz and 125 Hz. On the other hand, the SPL are all negatives at frequency 1000 Hz, 2000 Hz and 4000 Hz. In conclusion, SPL of breathing sounds of the participants, at frequencies 250 Hz and 500 Hz that have both positive and negative values are viable to be studied further for physiological and medicinal clues.