Quanta emission rate during speaking and coughing mediated by indoor temperature and humidity

IF 10.3 1区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environment International Pub Date : 2025-04-01 DOI:10.1016/j.envint.2025.109379

Vitor Lavor , Jianjian Wei , Omduth Coceal , Sue Grimmond , Zhiwen Luo

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引用次数: 0

Abstract

In epidemiological prospective modelling, assessing the hypothetical infectious quanta emission rate (E_q) is critical for estimating airborne infection risk. Existing E_q models overlook environmental factors such as indoor relative humidity (RH) and temperature (T), despite their importance to droplet evaporation dynamics. Here we include these environmental factors in a prospective E_q model based on the airborne probability functions with emitted droplet distribution for speaking and coughing activities. Our results show relative humidity and temperature have substantial influence on E_q. Drier environments exhibit a notable increase in suspended droplets (cf. moist environments), with E_q having a 10-fold increase when RH decreases from 90 % to 20 % for coughing and a 2-fold increase for speaking at a representative summer indoor environment (T = 25° C). In warmer environments, E_q values are consistently higher (cf. colder), with increases of up to 22 % for coughing and 9 % for speaking. This indicates temperature has a smaller impact than humidity. We demonstrate that indoor environmental conditions are important when quantifying the quanta emission rate using a prospective method. This is essential for assessing airborne infection risk.

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室内温度和湿度对说话和咳嗽过程中量子发射率的影响

在流行病学前瞻性建模中，评估假设的感染量子排放率（Eq）对于估计空气传播感染风险至关重要。现有的Eq模型忽略了环境因素，如室内相对湿度（RH）和温度(T)，尽管它们对液滴蒸发动力学很重要。在这里，我们将这些环境因素纳入基于空气传播概率函数的前瞻性Eq模型中，该模型具有说话和咳嗽活动的发射液滴分布。我们的研究结果表明，相对湿度和温度对Eq有实质性的影响。干燥环境中悬浮液滴显著增加（如潮湿环境），当RH从90 %降至20 %时，Eq增加10倍，在典型的夏季温度（T = 25°C）下，Eq值增加2倍。在温暖环境中，Eq值持续较高（如较冷），咳嗽时增加22. %，说话时增加9. %。说明温度的影响小于湿度。我们证明，室内环境条件是重要的量化时，使用前瞻性方法的量子排放率。这对于评估空气传播感染风险至关重要。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Environment International 环境科学-环境科学

CiteScore

21.90

自引率

3.40%

发文量

734

审稿时长

2.8 months

期刊介绍： Environmental Health publishes manuscripts focusing on critical aspects of environmental and occupational medicine, including studies in toxicology and epidemiology, to illuminate the human health implications of exposure to environmental hazards. The journal adopts an open-access model and practices open peer review. It caters to scientists and practitioners across all environmental science domains, directly or indirectly impacting human health and well-being. With a commitment to enhancing the prevention of environmentally-related health risks, Environmental Health serves as a public health journal for the community and scientists engaged in matters of public health significance concerning the environment.