Indoor Air Cartoon Journal, July 2019, Volume 2, #69

Have a safe trip! That will not occur if occupant in a vehicle feels uncomfortable due to unacceptable perceived air quality (PAQ) or exposure to poor indoor air quality (IAQ). Chemical or biological pollutants in the car could cause shortness of breath, dizziness, headache, nausea, eye, nose and throat irritations, and more symptoms.  The symptoms can be referred to as sick vehicle syndrome (SVS). SVS occurs when vehicle occupants manifest symptoms that cannot be specifically attributed to a particular exposure in the vehicle. The symptoms usually disappear, or their intensity reduces when occupants leave the vehicle.

Similar to a building, adequate ventilation rate is essential to reduce the concentration of the pollutants in the vehicle or the intensity of poor PAQ. It is expected that the higher the ventilation rate, the lower will be the intensity of SVS symptoms. The assumption is that the supplied outdoor air is clean. However, outdoor air quality on the roads, especially busy roads, are usually of poor quality. Adoption of appropriate filter will reduce outdoor to indoor transport of outdoor air pollutants. The air-conditioned vehicle usually recirculates a larger proportion of its air. The number of times pollutants in the car pass through a filter, the higher the tendency of delivering clean air. Any air cleaning strategy adopted should not release pollutant into the car.

Elimination of source, e.g. cigarette or volatile organic compounds emitter, or any environmental conditions, e.g. temperature or relative humidity, should be adequately controlled or eliminated to avoid unwanted emission of pollutants or odour.

Are you interested in this topic? Read the papers in the reference section and reflect on what they mean to a healthy vehicle.