Weighing imprecision and handleability of the sampling cassettes of the IOM sampler for inhalable dust
Weighing imprecision and handleability of the sampling cassettes of the IOM sampler for inhalable dust
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DOI：
10.1016/s0003-4878(00)00052-1
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发表时间：
2001-04-01
影响因子：
--
通讯作者：
Bergman, G
中科院分区：
文献类型：
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作者：
Lidén, G;Bergman, G
通过多次称量试验，对IOM吸尘采样器采样盒的重量稳定性进行了测试。结果表明，重复称量的可靠性较好，但水蒸气吸收较慢，不同盒式样品的水蒸气吸收差异较大。吸水的指数时间常数约为4天，需要15-20天才能获得稳定的重量。在磁带空白的帮助下，如果允许磁带在称重前、称重前和取样后在称重室储存一周，则粉尘重量的不精确度可以控制在0.05毫克以下。国际移民组织的采样盒似乎由几个子集组成，每个子集在称量室中的相对重量增加相同。为了保持较低的可变性，重要的是用于采样的空白和盒式磁带都来自同一子集。实验表明，IOM取样盒的导电塑料可以用另一种导电性相近但吸湿率低30倍的塑料代替。设计了一个与盒式磁带称重的盖子，以消除盒式磁带本身对商业运输夹子潜在的灰尘损失。设计了一种流量适配器，简化了个人采样过程中空气流量的测量。(C)2001年英国职业卫生协会。爱思唯尔科学有限公司出版。版权所有。
The weight stability of the sampling cassette of the IOM sampler for inhalable dust was tested in several weighing experiments. The results show that the reliability of repeated weighings was good, but the absorption of water vapour was slow and varied considerably among cassette specimen. The exponential time constant for water absorption was approximately 4 days, and 15-20 days were needed to obtain weight stability. With the help of cassette blanks the imprecision in dust weight could be held below 0.05 mg, if the cassettes were allowed one week's storage in the weighing room before weighing, both before and after sampling. The IOM sampling cassettes seem to consist of a few subsets, each with identical relative weight increase in a weighing room. To keep the variability low it is important that both the blanks and the cassettes used for sampling come from the same subset. Experiments indicate that the conducting plastic of the IOM sampling cassette may be replaced with another kind of plastic with similar electrical conductivity, but whose humidity absorption is 30 times lower. A lid, which is weighed with the cassette, was designed so that the potential dust loss from the cassette proper to the commercial transport clip was eliminated. A flow adapter, which simplifies the measurement of the air flow during personal sampling, was designed. (C) 2001 British Occupational Hygiene Society. Published by Elsevier Science Ltd. All rights reserved.