Assessing High-Noise Areas
Industrial hygienists are challenged to protect employees from noise exposure in all types of work environments, including variable conditions. This project completed a baseline noise assessment at the Dow Northeast Technology Center’s mechanical areas.
Noise is a ubiquitous hazard present in workplaces that can be difficult to characterize in variable work environments. Work-induced hearing loss, one of the most prevalent occupational illnesses, is a result of repetitive high noise exposure. In addition to hearing loss, workers who are overexposed to noise are at risk for developing hypertension.
OSHA indicates that a personal exposure level exceeding 85 dBA requires enrollment of the exposed worker in a hearing conservation program. Companies have the responsibility to assess noise levels and determine whether adequate protections exist to maintain workers’ health. Industrial hygienists are challenged to protect employees from noise exposure in all types of work environments, including variable conditions and newly commissioned facilities. In work environments that cannot be remediated to reduce levels below the OSHA action level, personal protective equipment (PPE) is required to protect employees.
Research was completed at the new Dow Northeast Technology Center in Collegeville, Pa. (shown in the photo accompanying this article), by utilizing an in-house noise mapping tool. This study completed a baseline sound level assessment within the mechanical areas to assist in the identification of sources and areas needing exposure controls. This study addressed potentially at-risk workers, including all Dow Chemical employees and contractors who work in the mechanical areas at the Collegeville location. These workers include mechanics, electricians, carpenters, plumbers, ironworkers, laborers, engineers, and inspectors. Dow Chemical, like many other companies, defers to ACGIH’s eight-hour TWA of 85 dBA with a 3 dBA doubling factor, because current occupational data show these values are more protective. Exposure control implementation was completed in all work areas exceeding 85 dBA.
The Dow Physical Agent Mapping Tool was used to elucidate spatial patterns. This software produces visual aids to depict sound levels within the mapped area. Area noise surveys were completed in a grid pattern, and the data were entered into the mapping tool. Excessive noise areas were defined by noise levels > 85 dBA. The Casella USA Model CEL-62X sound level meter was used to measure the noise levels. The CEL-62X was calibrated before and after each sampling period to 114dBA using the Casella USA CEL-284/2 acoustical calibrator; the instrument remained within the respective calibration range throughout the sampling period.
This article originally appeared in the May 2016 issue of Occupational Health & Safety.