Abstract Oxygen Deficiency Hazard (ODH) poses a serious occupational risk, and represents a frequent cause of incidents, accidents, and fatalities, mostly in confined spaces and laboratories. Besides these working environments, there is a large spectrum of industries that need to manage the asphyxiation risk caused by extensive inert gas uses. In such a context, mathematical models represent a valuable tool for characterising exposure profiles under varying conditions and evaluating several exposure scenarios, prospectively or retrospectively, for new processes and/or non-routine events. To this end, the objectives of this paper are to: (1) define a traditional Near Field-Far Field (NF-FF) model to estimate the indoor oxygen (O2) concentration percent by volume and partial pressure, and (2) develop a spreadsheet workbook, called ODHMOD, for supporting occupational hygienists, safety and health practitioners, and risk assessors during ODH assessments. Both the NF-FF model and ODHMOD employ data and information usually available in companies, and predict the O2 levels time trends in working environments where inert gas releases can occur, and forced and natural ventilation can move airflows inside and/or outside. The mathematical model and its implementation in Microsoft® Excel are described, with an example of its application in a possible industrial scenario.

中文翻译：

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基于传统近场-远场方法的模型和用于管理缺氧危害的电子表格工作簿

摘要 缺氧危害 (ODH) 是一种严重的职业风险，是事故、事故和死亡的常见原因，主要发生在密闭空间和实验室。除了这些工作环境之外，还有很多行业需要管理因广泛使用惰性气体而导致的窒息风险。在这种情况下，数学模型代表了一种有价值的工具，可用于表征不同条件下的暴露情况，并针对新过程和/或非常规事件前瞻性或回顾性地评估几种暴露情况。为此，本文的目标是：(1) 定义一个传统的近场-远场 (NF-FF) 模型来估计室内氧气 (O2) 的体积和分压浓度百分比，以及 (2) 开发一个名为 ODHMOD 的电子表格工作簿，用于在 ODH 评估期间支持职业卫生师、安全和健康从业人员以及风险评估人员。NF-FF 模型和 ODHMOD 均采用公司通常可获得的数据和信息，并预测可能发生惰性气体释放的工作环境中的 O2 水平时间趋势，并且强制和自然通风可以将气流移动到内部和/或外部。描述了数学模型及其在 Microsoft® Excel 中的实现，并举例说明了其在可能的工业场景中的应用。强制和自然通风可以将气流移动到内部和/或外部。描述了数学模型及其在 Microsoft® Excel 中的实现，并举例说明了其在可能的工业场景中的应用。强制和自然通风可以将气流移动到内部和/或外部。描述了数学模型及其在 Microsoft® Excel 中的实现，并举例说明了其在可能的工业场景中的应用。