확산식 시료채취기에서 기류제어막 공극 크기에 따른 시료채취율의 변화특성에 관한 연구

Abstract

Windscreen of the passive sampler plays critical role to obtain constant sampling rates. To minimize the variation of the sampling rates, smaller pore size of the windscreen would show better performance. However, it is desirable to collect a large amount of the target analytes as much as possible. It can be achievable to increase the sampling rate. In the viewpoint of the sampling rate, thus, larger pore size of the windscreen is preferable. Therefore, there is a tradeoff between the sampling rate and variation. Several filters having different pore sizes ( 11 ㎛, 20 ㎛, 60 ㎛, 100 ㎛, 140 ㎛ and 180 ㎛) were tested in this study to investigate the relationship between the increase of the sampling rate and variation. Tested filters were replaced with the windscreen of the 3M OVM #3500 badge. Those tested passive samplers installed with various windscreens were tested in the chamber against benzene, toluene, and o-xylene. 1. Same level of sampling rates were shown for all the filters with no apparent air movement in the chamber during sampling period. 2. Both the random variation and magnitude of the sampling rates were increased as the pore size of the windscreen increased. Passive samplers installed the windscreen of the pore size of 11 and 20 ㎛ showed less than 5% sampling rate error that is the recommended maximum sampling rates error by the NIOSH. 3. Sampling rates with the windscreen of the pore size of 11 ㎛ were 36.8 cc/min for benzene, 32.6 cc/min for toluene, and 30.4 cc/min for o-xylene respectively. 4. Sampling rates with the windscreen of the pore size of 20 ㎛ were 38.2 cc/min for benzene, 33.0 cc/min for toluene, and 31.0 cc/min for o-xylene respectively. 5. Sampling rates for 3M OVM #3500 badge were 35.4 cc/min for benzene, 31.2 cc/min for toluene, and 29.5 cc/min for o-xylene respectively. These values were similar to the sampling rates provided by 3M(35.5 cc/min, for benzene, 31.4 cc/min for toluene, and 27.3 cc/min for o-xylene).