Saturday, February 14, 2015

Traffic Lights have High Pollution

Traffic Lights have High Pollution

Researchers at the University of Surrey have found that where drivers spend just 2% of their journey time passing through traffic intersections managed by lights, this short duration contributes to about 25% of total exposure to these harmful particles [1].

In their survey, the team followed and assayed the level of pollution faced by driver on their day routes. The findings are:

1.  Signalized traffic intersections were found to be high pollution hot-spots.

2. De-accelerating, stopping and then starting/reviving the engine contributed to a sudden rise in the particle concentration, as much as 29% compared to normal traffic flow.

3. As vehicles are parked closer on traffic intersections, the per unit concentration is even more.

4. The best way is to avoid busy intersections, but all else fail, then keep windows shut, turn off fans and keep vehicles at distance from neighbours.

5. Pedestrians too suffer on similar scale, so they should avoid busy intersections.


1. Kumar, P.; et. al. Characterisation of nanoparticle emissions and exposure at traffic intersections through fast–response mobile and sequential measurements. Atmospheric Environment 2015; DOI: 10.1016/j.atmosenv.2015.02.002

Conclusion: I am now understand why we Indians are always jumping red-lights. We are safe-guarding against vehicular pollution !!!!!