Empirical Studies Assessing the CO₂ Levels in Indoor Spaces

Abstract

The COVID-19 pandemic forced everyone to isolate themselves and confine their lives to enclosed spaces to protect themselves from the outbreak and spread of the virus. Contrary to this, recent studies have shown that restricting ventilation in a space can lead to health risks resulting from CO₂ build-up from exhaled breath. There have also been a substantial number of multidisciplinary research studies that have established CO₂ exhalation in an enclosed room as a proxy for COVID-19 and other similar variants of viruses. We conducted experiments to understand the spatio-temporal spread of CO₂ inside a car in the hot and dry climate of Jodhpur and a bedroom in the composite climate of New Delhi during the winter season. The experiments were carried out using reference-grade sensors and custom-built devices for indoor use, which measured the ambient temperature, relative humidity, and CO₂ levels. On analyzing the findings from our studies, we observed that even seemingly harmless situations, such as an enclosed vehicle and a non-ventilated bedroom space, could lead to harmful levels of CO₂ built-up of over nine times and three times over the acceptable threshold of 1000 ppm for a car and a bedroom, respectively. Reassessment of the design guidelines underlying environmental ergonomics is advised for automobiles and residential spaces.