A Method to Evaluate an Air Purification System in Public Transport Buses 2023-28-0041

In India, around 70 million people travel by public transport buses. With rising air pollution across cities, there is a need to safeguard passengers from inhaling polluted air. Contaminants in such polluted air could be fine to coarse dust (2.5 micron to 100 micron), exhaust gases (oxide of sulphur, nitrogen and carbon), total volatile organic compounds, bacteria and viruses arising out of covid-19 pandemic. Passengers commuting in buses are continuously inhaling air that is re-circulating through the Air Conditioning system (AC) and also comes in contact with multiple co-passengers and touch points. This air potentially carries a high dose of contaminants and inhalation of such air can lead to health issues.

Vehicle manufacturers intend to provide clean air inside the vehicle cabin by configuring various Air Purification systems (AP) which reduce air contaminants in the closed space of a cabin. Currently, the technology and concepts for Air Purification systems continue to be adapted from existing stationary applications such as homes, buildings and office areas.

Test conditions for assessing the performance of Air Purification systems in stationary and automotive applications are different. The challenge therefore lies in developing an appropriate validation approach to assess Air Purification system in automotive application considering real-world scenarios.

This study discusses a comprehensive objective method to evaluate the performance of an Air Purification system deployed on buses, equipped with an air conditioning system. It examines the selection of test cases, test cycles and ambient conditions that can be applied on a prospective Air Purification system with a view to minimize dust and gaseous contaminants in the cabin. The test results once obtained, will assist vehicle manufacturers to identify areas of improvements in their product and develop a lineup of actions and solutions to enhance Vehicle Interior Air Quality (VIAQ), which will safeguard passengers from air contaminants inside the vehicle cabin. The outcome of this work will assist vehicle manufacturers to establish a structured validation process for evaluation of an Air Purification system