Estimation of required monitoring time for obtaining validation data in enclosed spaces.
Estimation of required monitoring time for obtaining validation data in enclosed spaces.
复制标题
估计在封闭空间内获取验证数据所需的监测时间。
DOI：
10.1039/b806421k
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Slaven,JamesE
中科院分区：
文献类型：
--
作者：
Lee,EunGyung;Feigley,CharlesE;Hussey,JamesR;Slaven,JamesE
估算封闭空间内特定位置空气污染物浓度的方法，如数学模型和计算流体动力学（CFD），通常根据直接测量的浓度进行验证。然而，浓度随时间的变化将不确定性引入测量浓度。未能确定监测时间要求可能会导致代表性浓度的定量错误，这可能归因于正在验证的方法中的错误。在本研究中，为了使用直接阅读仪器获得多个位置的代表性浓度，我们使用标准偏差比（SDR）方法来确定规定精密度限值内所需的最短监测时间。为了证明SDR方法在构建精度置信区间中的使用，测量了实验室中9个采样位置的示踪气体浓度，以获得总体参数。采用0.9、3.3和5.5 m3 min-1的三种流速，并使用光电离分析仪测量污染物浓度。监测时间要求随室内位置的不同而变化很大，并且强烈依赖于通过室内的空气流速。所提出的方法将是非常有用的工业化学家和室内空气研究人员谁有时需要获得数百个测量浓度的验证目的，或在可重复的条件下进行测试，在封闭的空间。这项研究还表明，所提出的方法可以用来设计有效的室内监测策略。
Methods for estimating airborne contaminant concentrations at specific locations within enclosed spaces, such as mathematical models and computational fluid dynamics (CFD), often are validated against directly measured concentrations. However, concentration variation with time introduces uncertainty into the measured concentration. Failure to determine monitoring time requirements can lead to errors in quantifying representative concentrations, which are likely to be attributed to errors in the method being validated. In the current study, to obtain the representative concentrations at multiple locations with a direct reading instrument, we used the standard deviation ratio (SDR) method to determine the required minimum monitoring time within a specified precision limit. To demonstrate the use of the SDR approach in constructing precision confidence intervals, tracer gas concentrations at nine sampling locations in an experimental room were measured to obtain population parameters. Three flow rates of 0.9, 3.3 and 5.5 m3 min−1 were employed and contaminant concentrations were measured using a photoionization analyser. Monitoring time requirements varied substantially with location within the room and were strongly dependent upon the flow rate of air through the room. The proposed method would be very useful for industrial hygienists and indoor air researchers who sometimes need to obtain several hundred measured concentrations for validation purposes or to perform tests under repeatable conditions in enclosed spaces. This study also showed that the proposed method can be used to devise efficient indoor monitoring strategies.