Anand S, Sreekanth B, Mayya Y S
a Health Physics Division, Bhabha Atomic Research Centre , Trombay , Mumbai , India .
b Radiation Safety Systems Division, Bhabha Atomic Research Centre , Trombay , Mumbai , India , and.
Inhal Toxicol. 2016;28(1):39-47. doi: 10.3109/08958378.2015.1130759. Epub 2016 Jan 21.
Role of Ultra-fine Particles (UFPs) in causing adverse health effects among large population across the world, attributable to household smoke, is being increasingly recognized. However, there is very little theoretical perspective available on the complex behavior of the UFP metrics with respect to controlling factors, such as ventilation rate and particle emission rate from the combustion sources. This numerical study examines through coagulation dynamics, the dependence of UFP metrics, viz., number (PN), mass (PM(0.1)) and surface area (PA(0.1)) concentrations below 0.1 μm diameter, on ventilation and the number emission rate from household smoke. For strong sources, the steady-state concentrations of these metrics are found to increase initially with increasing Air Exchange Rate (AER), reach a peak value and then decrease. Counter correlations are seen between UFP metric and PM(2.5) concentrations. The concepts of Critical Air Exchange Rate (CAER) and Half-Value Air Exchange Rate (HaVAER) have been introduced which indicate a feasibility of mitigation of PM(0.1) and PA(0.1), unlike PN, by ventilation techniques. The study clearly brings forth complex differential behavior of the three UFP metrics. The results are further discussed.
超细颗粒物（UFPs）在导致全球大量人口健康不良影响方面的作用越来越受到认可，这归因于家庭烟雾。然而，关于超细颗粒物指标在诸如通风率和燃烧源颗粒物排放率等控制因素方面的复杂行为，几乎没有理论观点。本数值研究通过凝聚动力学，研究了直径小于0.1μm的超细颗粒物指标，即数量（PN）、质量（PM(0.1)）和表面积（PA(0.1)）浓度，对通风和家庭烟雾排放率的依赖性。对于强源，发现这些指标的稳态浓度最初随着空气交换率（AER）的增加而增加，达到峰值后下降。超细颗粒物指标与PM(2.5)浓度之间存在反相关关系。引入了临界空气交换率（CAER）和半值空气交换率（HaVAER）的概念，这表明通过通风技术减轻PM(0.1)和PA(0.1)（与PN不同）是可行的。该研究清楚地揭示了三种超细颗粒物指标的复杂差异行为。对结果进行了进一步讨论。
