焊接高级 REACH 工具（weldART）的校准。

Calibration of the Welding Advanced REACH Tool (weldART).

机构信息

Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, UK; Faculty of Science, Ubon Ratchathani University, Ubon Ratchathani, 34190, Thailand.

Centre of Excellence in Sustainable Building Design, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, UK.

出版信息

Int J Hyg Environ Health. 2020 Jun;227:113519. doi: 10.1016/j.ijheh.2020.113519. Epub 2020 Apr 6.

DOI:10.1016/j.ijheh.2020.113519

PMID:32272436

Abstract

OBJECTIVES

This paper reports a study to develop and calibrate a deterministic model of welding fume exposure based on a four-compartment mass-balance model - The Welding Advanced REACH Tool (weldART). To achieve this aim, measurements of welding fume exposure were collected along with data on exposure determinants needed in the modelling.

METHODS

The welding fume exposure data was obtained from workers in a structural steel fabrication plant. Welders were engaged in three processes: flux-cored arc welding (FCAW), shielded metal arc welding (SMAW) and gas tungsten arc welding (GTAW). Aerosol concentration was measured using 13 mm diameter Swinnex sampling heads and MicroPEM direct-reading aerosol monitors. The model was initially developed with three spatial compartments (near-field (NF), far-field (FF), and welding plume (WP)). However, in the welding scenario investigated the FF had a very large volume and it was necessary to subdivide the room volume into an intermediate zone representing the FF along with the remaining room zone (RM). We fitted linear equations forced through the origin to the gravimetric concentrations measured inside the welders' visor and the weldART model estimates. The flowrates between the model compartments were adjusted by trial and error to obtain proportionate concentrations in each compartment.

RESULTS

The FCAW process generated higher welding fume particulate concentrations than SMAW and GTAW. The MicroPEM monitors considerably underestimated and were poorly correlated with the corresponding data from the Swinnex samplers. It was concluded that the MicroPEM data were unreliable. The model calibration showed a strong association between the personal exposure measurement and the weldART model values (R = 0.94), with the average estimated value 1.3 times the measurements. The NF and the FF model estimates were poorly correlated with the corresponding compartment measurements (R = 0.37 and 0.35, respectively), although on average the model estimates were close to the measurement data (ratio of modelled to measured 0.9, and 1.0, respectively).

CONCLUSIONS

The calibration shows that the weldART model is able to predict the exposure of welding fume particulate.

摘要

目的

本研究旨在开发和校准基于四 compartment 质量平衡模型-焊接高级 REACH 工具（weldART）的焊接烟尘暴露的确定性模型。为了实现这一目标，收集了焊接烟尘暴露测量值以及建模所需的暴露决定因素数据。

方法

焊接烟尘暴露数据来自结构钢制造工厂的工人。焊工从事三种工艺：药芯焊丝电弧焊（FCAW）、金属极惰性气体保护电弧焊（SMAW）和钨极惰性气体保护电弧焊（GTAW）。使用 13mm 直径的 Swinnex 采样头和 MicroPEM 直接读数气溶胶监测器测量气溶胶浓度。该模型最初开发时有三个空间隔（近场（NF）、远场（FF）和焊接羽流（WP））。然而，在所研究的焊接场景中，FF 具有非常大的体积，因此有必要将房间体积细分为代表 FF 的中间区域以及剩余的房间区域（RM）。我们拟合了穿过原点的线性方程，以拟合测量焊工面罩内的重量浓度和 weldART 模型估计值。通过反复试验调整模型隔室之间的流量，以在每个隔室中获得成比例的浓度。

结果

FCAW 工艺产生的焊接烟尘颗粒物浓度高于 SMAW 和 GTAW。MicroPEM 监测器大大低估了与 Swinnex 采样器相对应的数据，相关性也很差。得出的结论是 MicroPEM 数据不可靠。模型校准显示个人暴露测量值与 weldART 模型值之间存在很强的关联（R=0.94），平均估计值是测量值的 1.3 倍。NF 和 FF 模型估计值与相应隔室测量值的相关性较差（分别为 R=0.37 和 0.35），尽管模型估计值平均接近测量数据（模型与测量的比值分别为 0.9 和 1.0）。