Atlas de l'exposition aux pollutions atmosphérique et sonore

Main Findings

Travelling in Montreal during rush hours: The car is not significantly faster

On average, for the trips made, the travel times are 38 minutes for car users, 39 minutes for cyclists, and 42 minutes for public transit users. The statistical tests conducted show that there are no significant differences between the three methods of transportation. Consequently, using a car during rush hours in Montreal for trips of about 45 minutes is not faster than travelling by bike or public transit. In other words, cycling and public transport are effective alternatives to the car during rush hours. Indeed, during the trips made, cyclists arrived on average one minute after car users, and public transit users arrived 4 minutes afterwards. Nor does this take into account the time required to park the car. It is also noteworthy that, for 25% of the trips, cyclists arrived before car users (5 minutes or less).
 

Travel times
(in minutes)
Difference from the mean
compared to the car (in minutes)

 

Noise exposure: Higher levels for public transit users and cyclists

On average, car users are exposed to noise levels of 66.9 dB(A), compared with 69 for cyclists and 73 for public transit users. This is a significant difference, which indicates that cyclists and, especially, public transit users are more exposed to this nuisance. The higher levels observed for public transit users are explained in particular by their use of the subway.
The World Health Organization (WHO) recommends that the outdoor noise guideline value of 55 dB(A) not be exceeded during the day. Moreover, in the policy on road traffic noise issued by the Quebec Ministry of Transport, it is recommended that noise not exceed 65 dB(A) along traffic lanes. These values were clearly surpassed, whatever the mode of transportation used.

 

Air pollution (NO2) exposure: No significant differences, and values far below World Health Organization (WHO) recommendations

On average, for the trips made, the levels of exposure to nitrogen dioxide (NO2) are, respectively, 97, 101 and 96 μg/m3 for car users, cyclists and public transit users.There are no significant differences between these means. In other words, exposure to this pollutant is not higher for cyclists and public transport users than for car users. It should be emphasized that the observed levels of exposure are much (2 times) lower than the threshold of 200 μg/m3 recommended by the World Health Organization (WHO).

 

Inhalation of the NO2 pollutant: Much higher levels for cyclists

Although exposures to the NO2 pollutant are comparable among the different modes of transport, cyclists inhale nearly 3 times more of the pollutant than car users. Indeed, cyclists have higher ventilation rates. In other words, they breathe more litres of air per minute into their lungs and thus inhale more air pollutants.

 

The two graphs below clearly show that cyclists’ heart and respiration rates are much higher, which explains the higher levels of inhalation.

 

Much higher physical activity levels for cyclists

It is no surprise that physical activity levels and caloric expenditure are much higher for cyclists than for car users.

 

Summary of results

The results of the research project show that:

  1. Travel times are not significantly different among the three modes of transport;
  2. Public transit users’ and cyclists’ levels of exposure to noise are significantly higher than those of car users;
  3. Levels of exposure to the NO2 pollutant are not significantly different among the three modes of transport;
  4. Inhaled doses of the NO2 pollutant are 3 times higher for cyclists than for car users due to their stronger ventilation;
  5. It is not surprising that physical activity levels and caloric expenditure, as well as the health benefits, are much greater for cyclists than for car users.