Date of Award
MS Industrial Hygiene
During abrasive blasting, the operator is exposed to a process consisting of combined sound pressure levels from compressed air propelling an abrasive media through the hose, the abrasive striking metal substrate, the flow of breathing air inside the helmet, and the reverberation of sound inside the walls of the blast booth. The resulting noise can reach peak sound pressure levels (Lpeak) of 128 dBA, exceeding allowable occupational exposure levels.
The objectives of this study were to investigate the noise levels produced during abrasive blasting, attempt to further quantify total noise exposure to the abrasive blast operator, and calculate combined attenuation provided by the abrasive blasting helmets and hearing protection devices. The attenuation provided by the helmets alone was directly measured during abrasive blasting operations through personal dosimetry. The attenuation provided by the helmets when used in combination with hearing protection devices was determined by applying measured attenuation data from the helmets to the attenuation data provided by hearing protection device manufacturers. Findings of the study revealed that noise levels inside the blast booth were above the OSHA permissible exposure level while noise levels inside the helmets were attenuated to within allowable levels largely on account of helmet construction. Combined attenuation provided by the helmet and hearing protection device was significant enough to reduce noise exposure to below the occupational exposure limit of 90 dBA.
Lindsey, Michael, "AN ANALYSIS OF HELMET SOUND ATTENUATION DURING ABRASIVE BLASTING" (2016). Graduate Theses & Non-Theses. 84.