Track: Environmental Engineering

Abstract

A research was undertaken to explore sound levels in garments industries and their effects on the workers’ health and hearing, to test sound absorption capacity of different materials and to propose a design of a sound insulating sewing machine casing. Three industries were visited and workers’ health effect due to long time sound exposure were understood by questionnaire interview. Sound proofing efficacies of ply, Styrofoam, foam sheet and shine board were assessed, which were expressed by noise reduction coefficient (NRC). The NRC of the materials were respectively 0.06, 0.03, 0.05 and 0.03 in a single casing, 0.08, 0.04, 0.06 and 0.04 in a single casing with inclined partitions on inner wall and 0.11, 0.09, 0.11 and 0.06 for double casing with partitions of the same material and aggregates of foam particles between the walls of the casings. NRC of the ceramic material of Brothers Company sewing machine was found to be 0.09, a lesser value than the ply-foam combination. Button sewing machine was found to emit higher sound through the opening provided for easy circulation of thread tension lever. A casing for this opening was designed for full insulation system and providing safe and healthy working environment for garments workers.