Recorded at AIHce EXP 2021
Evaluation and Control of Ultrasound: Ultrasonic Welding
Historically, noise exposures measured from employees conducting ultrasonic welding operations a manufacturing facility were below the ACGIH TLV for audible noise. In addition, the employees working in the area did not observe any subjective effects associated with high frequency noise. However, other employees and/or visitors who would enter this area while ultrasonic welding was in motion did observe uncomfortable subjective effects. When it was shown noise exposures measured below the ACGIH TLV for audible noise, but above the ACGIH TLV for ultrasound, the facility implemented a simple engineering control which lowered the noise exposure well below the applicable ACGIH TLVs. The purpose of this presentation is to discuss the ACGIH noise evaluation criteria for audible noise and ultrasound, proper measurement techniques, and selection of an engineering control based from a case study addressing high frequency noise emitting from ultrasonic welding machines.
Presenter/Author: Mr, Anthony DiMaggio, CIH,Chubb Global Risk Advisors,Chicago, IL
Preliminary Evaluation of a Wearable Consumer Noise Measurement Device in the Laboratory and the General Indoor Environment
Over the past several years there have been a proliferation of applications ("apps") available for both the Apple and Android platform that can measure and integrate noise levels using the device's onboard micro-electro-mechanical system (MEMS) microphone. Regardless of the app or platform used, the physical characteristics and usage patterns of smart phones have made it difficult for these devices to be used for long-term personal noise measurements. Compared to the traditional dosimeter, the introduction of wearable devices equipped with a MEMS microphone provides the opportunity for relatively low-cost consumer grade devices to passively collect noise measurements without any input from the user, while simultaneously being able to alert the user of the presence of hazardous noise levels. This study is the first to evaluate the quality of noise measurements made by the first commercially successful wearable device, the Apple Watch, in both a controlled laboratory setting and in the general environment. Our findings suggest that the Apple Watch is capable of making reasonably accurate measurements, although these do not exactly follow the A-weighting curve and are not within the ANSI 2.0 dB tolerance for type 2 sound level meters. While these devices cannot be used for compliance measurements, they still provide a mechanism for researchers and occupational health professionals to greatly increase the amount of noise data that is collected at a relatively low cost.
Acknowledgements & References: NIOSH, Cincinnati, OH - for use of their acoustical laboratory
Co-Authors: N. Jacobs, Cardno ChemRisk, Arlington, VA C. Kardous, NIOSH, Cincinnati, OH H. Reamer, Cardno ChemRisk, Chicago, IL C. Mathis, Cardno ChemRisk, Arlington, VA S. Gaffney, Cardno ChemRisk, San Francisco, CA R. Neitzel, University of Michigan School of Public Health, Ann Arbor, MI
Presenter/Author: Author: Dr. Benjamin Roberts, Cardno ChemRisk,Chicago, IL