European Scientific Journal May 2016 edition vol.12, No.15 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 231 Sound Levels And Spectra At Ikot Uduak (MCC) Timber Market, Calabar, Cross River State, Nigeria Okoro, R.C. Bassey D.E. Umunnah, R.A. Electronics and Computer Technology Unit, Department of Physics, University of Calabar, Calabar doi: 10.19044/esj.2016.v12n15p231 URL:http://dx.doi.org/10.19044/esj.2016.v12n15p231 Abstract Acoustic and physical parameters of machines at Ikot Uduak timber market in Calabar, Cross River State, Nigeria were measured using a sound level meter and a real time frequency analyzer. The sound level meter was Mastech model MS6700. This has 30dB -130dB capability, with an accuracy of ± 1.5 dB. Real Time Audio Spectrum Analyzer, version 3.3 was used. The results showed that A-weighted sound levels with the meter at 1m away from the wood working machines were 100.5 dBA, 98.5 dBA, 98.2 dBA, 101.5 dBA and 90.5 dBA for Band saw, Table saw, Plainer, Spindle/Curving machine and the Drilling machine respectively. From this, the threshold for dangerous levels of noise, as stipulated by the Academy of Pediatrics and the National Campaign for Hearing and Health, which is 85 dB., and the Occupational Safety and Health Act (OSHA) permissible level of 90dBA for 8-hour day and 5 days a week, have been exceeded, and this could lead to hearing impairments. Keywords: Timber market, Wood working machines, Acoustic parameters, Sound level meter, A-weighted sound levels, Audio spectrum analyzer, Hearing impairment. 1. INTRODUCTION Sound is said to be disturbance which travels in form of an audible mechanical wave of pressure and displacement, through a medium such as air or water (WEC, 1969). Sound, occasionally, can be taken as vibrations with frequencies that are within the audio range of humans and some domestic animals (HMC, 2000). Such disturbances are produced by sound sources such as the vibrating diaphragm of a stereo speaker, barks from domestic animals and spoken communications with family and friends.