According to new UBC research, cyclists should ride at speeds between 12 and 20 km per hour on city roads, and pedestrians should walk at 2 to 6 km per hour to minimize their inhalation of air pollution while still getting the health benefits of exercise.
The faster people move, the harder they breathe and the more pollution they could potentially inhale, but they also are exposed to traffic for a shorter period of time.
In the study, UBC transportation experts used a U.S. Census-based computer model of 10,000 people to calculate ideal travel speeds that can minimize inhalation of polluted air.
The speeds are called the minimum-dose speeds (MDS) for different age and sex groups.
The researchers found that for female cyclists under 20, the ideal speed linked to the least pollution risk is 12.5 km per hour on average on a flat road. For male cyclists in the same age group, it’s 13.3 km per hour.
Ideal travel speeds were at 13 and 15 km per hour for female and male cyclists in the 20-60 age group.
Female and male pedestrians under 20 years old should be walking at speeds around 3 km per hour, while their older counterparts should look at reaching at least 4 km per hour, to breathe in the least amount of pollution over a trip.
If people move at much faster speeds than the MDS–say, cycling around 10 km faster than the optimal range–the inhalation of air pollution will be significantly higher.
The good news is, the MDS numbers align pretty closely with how fast most people actually travel.
The findings are described in a paper published recently in the International Journal of Sustainable Transportation.
Future research will validate the minimum-dose speed estimates with on-road data.
Citation: Bigazzi AY. (2016). Determination of active travel speed for minimum air pollution inhalation. International Journal of Sustainable Transportation, published online. DOI: http://dx.doi.org/10.1080/15568318.2016.1238984.
Figure legend: This Knowridge.com image is credited to University of British Columbia.