某型号个体采样器采样过程中流量变化规律的探讨

Discussion on Changing Rule of Flow-rate of Personal Sampler during Sampling Process

目的探讨某型号个体采样器采样过程中流量变化规律。方法分别测量不同型号、不同规格炭管管口水平放置、管口向上竖直放置和管口向下竖直放置3种情况下,不同采样时间的流量,比较流量的变化规律。结果无论何种炭管及如何放置,采样流量均随采样时间的增加而增加;炭管管口向下放置时,流量随时间的增加速度稍高于其他两种情况;在炭管不同放置情况下,用采样和不采样炭管测得的流量变化基本相同或不采样炭管流量变化略高于采样炭管;炭管管口水平放置和管口向上竖直放置时流量均值比较,差异均无统计学意义(P>0.05);管口向下放置时两组均数比较,差异均有统计学意义(P<0.05)。结论使用国产某型号个体采样器及活性炭管采样时,应注意炭管放置情况,只能水平放置或管口向上竖直放置,而不能管口向下竖直放置;同时,采样时间最好控制在4 h以内。

Objective To explore the changing regularity of flow-rate of a certain type personal sampler during sampling process.Methods The flow-rates at different sampling time were measured when the carbon tubes from different sampler types and different specifications were pointing horizontally,vertically upward,and vertically downward for three minutes.The changing rule of the flow-rate was compared.Results No matter which types of the carbon tube were used and how they were placed,the volumetric flow sampled increased with the increase of the sampling time.When the carbon tube was pointing vertically downward,the volumetric flow increase was a little bit quicker than other two patterns.Under different patterns of placement,the volumetric flow of either sampling or non-sampling carbon tubes were basically same,or that of the non-sampling tube was a little bit higher than that of the sampling tube.The mean values of volumetric flow were nearly the same when the tubes were placed horizontally and vertically upward,the difference was not significant（P0.05）.When the mean values of two groups of tubes placed vertically downward were compared,the difference was significant（P0.05）.Conclusions When this type of domestic made personal sampler and active carbon sampling tube are used,attention should be paid on the placement of the sampling tube.The tube should only be placed horizontally or vertically upward,and should not be placed vertically downward.The sampling time should be better controlled within 4 hours.