Sousan Sinan, Koehler Kirsten, Hallett Laura, Peters Thomas M
Department of Occupational and Environmental Health, University of Iowa, Iowa City, Iowa, USA.
Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
Aerosol Sci Technol. 2016;50(12):1352-1365. doi: 10.1080/02786826.2016.1232859. Epub 2016 Sep 7.
We compared the performance of a low-cost (∼$500), compact optical particle counter (OPC, OPC-N2, Alphasense) to another OPC (PAS-1.108, Grimm Technologies) and reference instruments. We measured the detection efficiency of the OPCs by size from 0.5 to 5 μm for monodispersed, polystyrene latex (PSL) spheres. We then compared number and mass concentrations measured with the OPCs to those measured with reference instruments for three aerosols: salt, welding fume and Arizona road dust. The OPC-N2 detection efficiency for monodispersed was similar to the PAS-1.108 for particles larger than 0.8 μm (minimum of 79% at 1 μm and maximum of 101% at 3 μm). For 0.5-μm particles, the detection efficiency of OPCN2 was underestimated at 78%, whereas PAS-1.108 overestimated concentrations by 183%. The mass concentrations from the OPCs were linear (r ≥ 0.97) with those from the reference instruments for all aerosols, although the slope and intercept were different. The mass concentrations were overestimated for dust (OPC-N2, slope = 1.6; PAS-1.108, slope = 2.7) and underestimated for welding fume (OPC-N2, slope = 0.05; PAS-1.108, slope = 0.4). The coefficient of variation (CV, precision) for OPC-N2 for all experiments was between 4.2% and 16%. These findings suggest that, given site-specific calibrations, the OPC-N2 can provide number and mass concentrations similar to the PAS-1.108 for particles larger than 1 μm.
我们将一款低成本（约500美元）的紧凑型光学粒子计数器（OPC，OPC-N2，Alphasense公司）与另一款OPC（PAS-1.108，格林科技公司）以及参考仪器的性能进行了比较。我们针对粒径范围为0.5至5μm的单分散聚苯乙烯乳胶（PSL）球体，测量了OPC的检测效率。然后，我们将使用OPC测量的三种气溶胶（盐、焊接烟尘和亚利桑那道路扬尘）的数量浓度和质量浓度，与使用参考仪器测量的结果进行了比较。对于粒径大于0.8μm的颗粒，OPC-N2的单分散检测效率与PAS-1.108相似（在1μm时最低为79%，在3μm时最高为101%）。对于0.5μm的颗粒，OPC-N2的检测效率被低估至78%，而PAS-1.108则将浓度高估了183%。尽管斜率和截距不同，但所有气溶胶的OPC质量浓度与参考仪器的质量浓度呈线性关系（r≥0.97）。对于扬尘，质量浓度被高估（OPC-N2，斜率=1.6；PAS-1.108，斜率=2.7），而对于焊接烟尘则被低估（OPC-N2，斜率=0.05；PAS-1.108，斜率=0.4）。在所有实验中，OPC-N2的变异系数（CV，精密度）在4.2%至16%之间。这些结果表明，经过特定地点的校准后，对于粒径大于1μm的颗粒，OPC-N2能够提供与PAS-1.108相似的数量浓度和质量浓度。
