In a business as usual scenario, atmospheric carbon dioxide concentration (CO₂) could reach 950 parts per million (ppm) by 2100. Indoor CO₂ concentrations will rise consequently, given its dependence on atmospheric CO₂ levels. If buildings are ventilated following current standards in 2100, indoor CO₂ concentration could be over 1300 ppm, depending on specific ventilation codes. Such exposure to CO₂ could have physiological and psychological effects on building occupants. We conducted a randomized, within-subject study, examining the physiological effects on the respiratory functions of 15 persons. We examined three exposures, each 150 min long, with CO₂ of: 900 ppm (reference), 1450 ppm (decreased ventilation), and 1450 ppm (reference condition with added pure CO₂). We measured respiratory parameters with capnometry and forced vital capacity (FVC) tests. End-tidal CO₂ and respiration rates did not significantly differ across the three exposures. Parameters measured using FVC decreased significantly from the start to the end of exposure only at the reduced ventilation condition (p < 0.04, large effect size). Hence, poor ventilation likely affects respiratory parameters. This effect is probably not caused by increased CO₂ alone and rather by other pollutants—predominantly human bioeffluents in this work—whose concentrations increased as a result.

中文翻译：

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暴露于中等水平二氧化碳的人的呼吸功能

在一切照旧的情况下，到 2100 年，大气二氧化碳浓度 (CO ₂ ) 可能达到百万分之 950 (ppm)。室内 CO ₂浓度将因此上升，因为它依赖于大气 CO ₂水平。如果建筑物按照 2100 年的现行标准进行通风，则室内 CO ₂浓度可能超过 1300 ppm，具体取决于特定的通风规范。这种暴露于 CO ₂可能对建筑物居住者产生生理和心理影响。我们进行了一项随机、受试者内研究，检查了对 15 人呼吸功能的生理影响。我们检查了 3 次暴露，每次 150 分钟，CO ₂的：900 ppm（参考）、1450 ppm（减少通风）和 1450 ppm（参考条件添加纯 CO ₂）。我们通过二氧化碳测定法和用力肺活量 (FVC) 测试测量了呼吸参数。三种暴露的呼气末 CO ₂和呼吸速率没有显着差异。仅在减少通风条件下，使用 FVC 测量的参数从暴露开始到结束显着降低（p  < 0.04，大效应量）。因此，通风不良可能会影响呼吸参数。这种影响可能不是由 CO ₂单独增加引起的，而是由其他污染物引起的——在这项工作中主要是人类生物废水——其浓度因此增加。