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Effectiveness of a Custom-fitted Flange and Local Exhaust Ventilation (LEV) System in Controlling the Release of Nanoscale Metal Oxide Particulates During Reactor Cleanout Operations

Abstract As the nanotechnology industry expands, facilities engaged in the production and use of engineered nanoscale materials (ENMs) are challenged with determining whether their processes pose a risk for worker inhalation exposure. Although there are neither regulatory exposure limits specific to ENMs nor validated measurement standards for nanomaterials in the workplace, many facilities opt to be proactive in managing uncharacterized ENMs by reducing or eliminating the potential for exposure by controlling their release into the workplace atmosphere. A field study was conducted to evaluate the effectiveness of a portable, HEPA-filtered, local exhaust ventilation system equipped with a custom-fitted flange for controlling the emission of engineered nanoscale metal oxide particulates during reactor cleanout operations. On the basis of the findings of this study, it appears that a properly designed LEV system, coupled with good work practices can be highly effective in controlling nanoscale material emissions during processes of this type.