A Low-cost Monitoring System for Enhanced Indoor Air Quality inside Built environment

Usage of ductless split conditioners inside built environment has seen a significant rise in tropical countries like India, as they provide thermal comfort. However, the absence of fresh air ventilation in ductless split conditioners has resulted in scenarios of CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentration above the ASHRAE threshold limit of $1000 \mathbf{p p m}$ for better indoor air quality and health. The study demonstrates the working principle of an IoT based automated system to provide ventilation during required periods to maintain better indoor air quality in an office type workspace. An Arduino Uno with wifi module measures the CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentration through a CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> sensor connected to it and transfers the data onto an online platform for data logging. Once the CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentration attains the upper limit, the system triggers the exhaust fan to provide fresh air ventilation until the CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentration decays to a preset lower limit. The results indicate that the automated system can be implemented to measure and maintain the average CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentration below 1000 ppm over a period of 8 hours.