No longer just a figurative form of speech, ‘Sick of waiting in traffic jams’, could literally be causing you to fall sick. Pollutants that gather inside cars while waiting in traffic jams or at red signal lights are significantly higher than when the car is moving. A simple solution is to keep the windows closed and to check that the air-dust filter in your vehicle is really functioning.
In 2013, the World Health Organization (WHO) identified outdoor air pollution as a major environmental risk to health and in cities it was classified as being as carcinogenic to humans as smoking was in 1985.
Air pollution contributes to lung cancer, asthma and other respiratory diseases and has been associated with heart disease and stroke. Air pollution was linked to over 3.7 million premature deaths worldwide in 2012.
New research shows that 25 percent of exposure to harmful particles when driving occurs in the two percent of journey time that drivers and passengers spend passing through intersections with traffic lights. At intersections, vehicles slow down, stop, rev up to move when lights turn green, and they are closer together.
This leads to levels of peak particle concentration at a signalized intersection that are 29 times higher than those found in free-flowing traffic. In addition, the cars move slowly, so that drivers are exposed for longer. As the output is ongoing, the pollution does not disperse but lingers and accumulates. As a result, cars waiting in traffic jams or at red lights contain up to 40 percent more pollution than those that are moving.
Results from the research showed that ventilation system of the car was efficient at removing coarse particles from the air, but as the concentration of coarse particles fell, the number of fine particles increased. The highest levels of pollution within the car tended to occur when the windows were closed at the traffic lights and the fan was on.
To reduce the amount of pollution exposure while waiting in traffic jams and at traffic lights, the study authors suggest that, motorists should close car windows and switch off the fan. This, they say, can reduce the chance of breathing in hazardous levels of air pollution by 76 percent. They also recommend setting the fan so that the air circulates internally. Recirculating the air prevents pollution from entering from outside. They also call for improving the efficiency of filtering systems of vehicles to further benefit vehicle occupants.
Other ways that local transport authorities could help alleviate the problem is by synchronizing traffic signals so as to reduce waiting time at signals and building more clover-leaf flyovers that reduce the need for signals and allows traffic to keep moving.