在人手中评估低频磁场诱导因子
Pia Schneeweiss1, Rene Hirtl1, Gernot Schmid1
1EMC & Optics, Seibersdorf Laboratories, Forschungszentrum, Seibersdorf, 2444, AUSTRIA.
Physics in medicine and biology
|August 29, 2025
概括
新研究建议修改手部暴露的磁感应因子, 可能缓解工作场所的限制. 这项研究更准确地评估了手部局部接触低频磁场的情况,确保了安全性,同时减少了不必要的限制.
科学领域:
- 职业健康和安全
- 电磁场 (EMF) 暴露的评估
- 生物物理
背景情况:
- 欧盟指令2013/35/EU要求通过将磁感应与肢体 (ALLimb) 的作用水平进行比较来评估职业低频磁场暴露.
- 超过ALLimb需要证明符合基于现场电场强度 (Êi,avg) 的暴露极限值.
- 目前的ALLimb的科学基础尚未确立,这引发了关于其局部手部暴露的保守性的问题.
研究的目的:
- 对于局部手部接触低频磁场,准确地得出最坏的诱导因子 (IF).
- 评估当前评估方法和手部模型对职业电磁场暴露的适用性.
- 提出一个可能更宽松的磁感应极限,减少不必要的工作场所的限制.
主要方法:
- 使用16个基于MRI的高分辨率解剖手的系统数值计算.
- 包含两个简化的手模型进行比较分析.
- 为代表成年男性的第95个百分点的手尺寸计算诱导因子 (IF).
主要成果:
- 强大的IF为0.6 (V/m) /T/Hz,用于第95百分点的男性手.
- 与当前的ALLimb相比,这种IF表明磁感应极限的潜在放松为33%.
- 过于简单的手模型显著低估了暴露,不适合剂量评估.
- 评估Ei,avg的99百分位而不是峰值空间Ei,avg导致局部暴露的低估.
结论:
- 导出的IF为评估局部手部暴露于低频磁场提供了更准确的基础.
- 一个修订的磁感应极限可以减少局部手部暴露的工作场所不必要的限制.
- 目前针对局部暴露的简化模型和评估方法需要重新评估,以确保准确的风险评估和工人保护.
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