Department of Occupational Medicine, Yazd University of Medical Sciences, Yazd, Iran.
Occup Med (Lond). 2009 Jun;59(4):267-9. doi: 10.1093/occmed/kqp033. Epub 2009 Mar 13.
Spot welding is a type of resistance welding in which pieces of metals are pressed together and an electric current is passed through them. Spot welders are at risk of contact with some potentially hazardous agents but there are few studies about the respiratory effects of spot welding.
Our objective was to study lung function and respiratory symptoms among spot welders and office workers at an automobile assembly factory in Iran.
This was a cross-sectional study of 137 male spot welders and 129 office workers. We used a questionnaire to record demographic data, smoking habits, work history and respiratory symptoms. Spirometry was performed to assess lung function status. Metal fume samples from the respiratory zone of spot welders were analysed.
The concentrations of metal fume were less than the American Conference of Industrial Hygienists (ACGIH) threshold limit values. There were significantly lower values for average forced expiratory volume in 1st second (FEV(1)), FEV(1)/forced vital capacity and 25-75% forced expiratory flow in spot welders compared to controls. There was also a significantly raised prevalence of respiratory symptoms (sputum and dyspnoea) in spot welders. Fifteen per cent of spot welders and 1% of controls had an obstructive pattern in spirometry.
Our survey suggests that spot welders are at risk of developing respiratory symptoms and decreasing pulmonary function values despite their exposure to components of welding fume being within ACGIH guidelines.
点焊是电阻焊的一种，其中金属片被压在一起，电流通过它们。点焊工有接触一些潜在危险物质的风险，但很少有研究点焊对呼吸的影响。
我们的目的是研究伊朗一家汽车装配厂点焊工和办公室工作人员的肺功能和呼吸症状。
这是一项对 137 名男性点焊工和 129 名办公室工作人员的横断面研究。我们使用问卷记录人口统计学数据、吸烟习惯、工作史和呼吸症状。使用肺量计评估肺功能状况。分析点焊工呼吸区的金属烟尘样本。
金属烟尘浓度低于美国工业卫生学家会议（ACGIH）的阈限值。与对照组相比，点焊工的平均 1 秒用力呼气量（FEV（1））、FEV（1）/用力肺活量和 25-75%用力呼气流量值明显较低。点焊工的呼吸症状（咳痰和呼吸困难）也明显增多。15%的点焊工和 1%的对照组在肺量计检查中出现阻塞性模式。
尽管我们的调查点焊工接触的焊接烟尘成分符合 ACGIH 指南，但仍有患呼吸症状和肺功能值下降的风险。
