Video techniques for monitoring exposure, such as NIOSH’s “Helmet-CAM,” employ both real-time dust monitors and mobile video cameras to assess workers’ respirable dust exposures. Many real-time personally worn dust monitors utilize light scattering sensing elements, which are subject to measurement biases as a function of dust type (size, composition, shape factor) and environmental conditions such as relative humidity. These biased and inaccurate dust measurements impair the monitor’s ability to properly represent actual respirable dust concentrations. In the testing described, instrument mass concentration data was collected using three different types of commonly used commercial off-the-shelf personal dust monitors and compared to a reference standard. This testing was performed in a calm air (Marple) dust chamber in which three units of each make and model (for a total of nine monitors) were used for each test. Equivalency factors (EF, a multiplier to match the Thermo TEOM 1400a reference instrument) ranged between 0.746 and 1.879 across all dusts and environmental conditions tested, and between 0.821 and 1.519 on the ISO test dust.

中文翻译：

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不同粉尘类型和湿度水平的实时光散射粉尘监测器的性能比较

监控暴露的视频技术，例如 NIOSH 的“头盔 CAM”，采用实时灰尘监视器和移动摄像机来评估工人的可吸入灰尘暴露。许多实时个人佩戴的灰尘监测器使用光散射传感元件，这些元件会受到作为灰尘类型（尺寸、成分、形状因素）和环境条件（例如相对湿度）的函数的测量偏差的影响。这些有偏差和不准确的粉尘测量会削弱监测器正确表示实际可吸入粉尘浓度的能力。在所描述的测试中，仪器质量浓度数据是使用三种不同类型的常用商用现成个人灰尘监测器收集的，并与参考标准进行比较。该测试是在平静空气 (Marple) 集尘室中进行的，其中每个品牌和型号的三个单元（总共九个显示器）用于每个测试。等效系数（EF，匹配 Thermo TEOM 1400a 参考仪器的乘数）在所有测试的灰尘和环境条件下介于 0.746 和 1.879 之间，在 ISO 测试灰尘上介于 0.821 和 1.519 之间。