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Estimating emmission factors in a capacitor factory using a modified two-zone model.

Schnaufer N; Do T; Lee E; Venkatraman M; Khan J
American Industrial Hygiene Conference and Exposition, May 13-16, 2006, Chicago, Illinois. Fairfax, VA: American Industrial Hygiene Association, 2006 May; :33-34
Various deterministic models have been used to estimate emission rates and emission factors. Here models were compared for estimating emission factors for isoamyl acetate (IAA) after dipping batches of capacitors to seal them. IAA concentrations were measured on three days with different production rates in the near-field and far-field using both charcoal tubes and diffusive samplers. Supply and exhaust air flowrates, and air speed and direction at various points near the source were measured as well. The two-zone model was selected as most applicable to the workroom studied and was adapted to improve the accuracy of emission rate estimates. This model's standard formulation for concentration in the near field is: C = (G/Q) + (G/B), where C is the near-field concentration, G is emission rate, Q is the flow of clean air into the workroom, and B is the rate of air exchange between the near and far fields. G/Q, which represents the far field concentration, was replaced by the average measured concentration upwind of the source. Also, B was calculated based on the average air speed toward the source and the cross-sectional area of the hemispherical near-field. The emission rates for the three days studied were: 1.5x10-2, 4.0x10-2 and 1.7x10-2 kg/hr corresponding to 10,24, and 14 dips during the sampling period. Thus, the emission factors were 9.5x10-3, 13x 10-3 and 9.1x10-3 kg/dip for an overall average of 10x10-3 kg/dip.
Models; Emission-sources; Chemical-properties; Sealing-compounds; Samplers; Air-flow
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American Industrial Hygiene Conference and Exposition, May 13-16, 2006, Chicago, Illinois
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University of South Carolina at Columbia, Columbia, South Carolina
Page last reviewed: August 26, 2022
Content source: National Institute for Occupational Safety and Health Education and Information Division