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 contamination within both the main glove box and pass-through. These results indicated that, although internal surfaces were contaminated with the materials, no leakage from the glove box was detected.



Figure 12. A glove box isolator for handling substances that require a high level of containment (Contains public sector information published by the Health and Safety Executive and licensed under the Open Government License v1.0.)

3.4.2.4 Air Curtain Fume Hood

A recent fume hood design addresses the known issues surrounding the recirculating flow patterns both inside the fume hood and around the operator (Figure 9). The air curtain-isolated fume hood, as shown in Figure 13, uses a push-pull ventilation configuration created by a narrow planar jet from the sash to an exhaust slot along the base of the hood opening. Tsai et al. [2010] evaluated the performance of this hood during handling and manipulation of nanoparticles. In this test, measurements in the worker's breathing zone were taken while nanoalumina powders were manually transferred or poured between several 400-ml beakers. The air-curtain hood had very low particle release during all tested conditions (i.e., varying sash heights) with low but measurable release occurring at the lowest sash position. This same study showed that the particle leakage from two traditional fume hoods (both a CAV and VAV hood) exhibited substantial particle release during similar nanomaterial handling operations. This study suggested that the air curtain isolated hood may provide better containment performance during typical handling procedures.

Current Strategies for Engineering Controls in Nanomaterial Production and Downstream Handling Processes

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