This study was performed to evaluate the performance of three passive samplers made in U.S.A. Three passive samplers selected for this study included products merle by 3M, Gilian, and SKC in U.S.A. Three organic solvents, such as toluene, trichloroethylene, and n-hexane which are used frequently in Korean industry were selected for the study. Conclusions obtained from this study are summarized as follows.
1. For toluene and trichloroethylene, the overall accuracy of the results from all of three products was within 25 %, which is the criteria recommended by the U.S. National Institute for Occupational Safety and Health (NIOSH). For n-hexane, the overall accuracy of the results from two products except 3M was exceeding 25 %. Thus 3M product showed the best accuracy among three products.
2. When passive samplers collected organic vapors were exposed to clean air for two hours, there were 12 - 16 % lass of organic vapors due to reverse diffusion in Gilian products. There was no significant loss in results from other two products.
3. Air velocity affected greatly on the performance of passive samplers which did not have permeation membrane. At high velocity, 100 ㎝/sec, accuracies of results from Gilian and SKC were 57 - 108 and 128 - 164 %, respectively. However, the results from 3M samplers, which contain permeation membrane, indicated accuracy below 25 %.
4. When passive samplers collected organic vapors for eight hours, the accuracy was reduced. Thus, it is recommended that passive samplers be used for less than four hours.
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