Study on Air-Circulation Practices in Car Cabin
Shaharin A. Sulaiman, Muhammad Khairul Adha M. Zali

Universiti Teknologi Petronas

Abstract

Extended use of recirculation air mode in a vehicle cabin may result in significant accumulation of carbon dioxide due to human exhalation and no inflow of fresh air. Consequently, this will affect their health and driving ability. On the contrary, allowing entrance of outdoor air into the cabin may expose the passengers to roadway contaminants and poor odor in polluted areas. It is a constant affirmation in Malaysia that using recirculation air mode during driving would result in the best thermal comfort. Unfortunately, there has been no report on passengers^ preference of their car air-conditioning operation. This study aims to investigate the present awareness on in-cabin air quality and the practices among passengers pertaining to ventilation of their car cabins. A set of survey question was circulated to 211 respondents on various aspects related to in-cabin conditions of air including how they manage their air-circulation systems. From the survey, it was found that most of the respondents (57%) chose recirculation mode in their everyday driving, 11% for outside air mode and 20% intermittently switched the two modes. Unfortunately, the majority of respondents were not aware that carbon dioxide levels could be high under prolonged recirculation mode. In addition, most of the respondents did not know that switching on the recirculation mode for too long could be dangerous for their health.

Keywords: in-cabin, indoor, air quality, ventilation

Topic: Transportation Safety