Make the Metro more comfortable, and commuters will come, researcher says

The newer AZUR trains on Montreal's Metro are an improvement over older trains when it comes to rider comfort, but they could still be better, especially when it comes to sound levels, according to a Concordia researcher.

Alireza Mohammadi estimates he's ridden the Metro for over 200 hours, on the Orange, Blue and Green lines, in old and new trains, in both the summer and winter, taking measurements for his work as a PhD candidate in civil engineering.

His efforts went toward creating what he describes as a comprehensive comfort assessment tool that can be used on public transit systems around the world.

Overall, he gives the new Azur trains a "good" rating out of a five-category scale, with "excellent" being the best, and "very poor" being the worst. However, the new trains only get a "fair" ranking when it comes to sound levels.

He ranks the older trains on the Metro overall as fair.

He hopes to help transit systems improve rider comfort in order to lure more people out of their cars, as municipalities focus on becoming more sustainable places to live and work.

His thesis supervisors suggested the topic, but he said his own frequent travels on the Green line in the older Metro cars made an impression on him.

"I was a daily traveller, so always I had a problem with thermal comfort during the winter, and also vibration and noise," he said.

Measuring, measuring

Mohammadi has been gathering data for about a year.

He rode the Metro lines end to end, starting in the morning and finishing in the afternoon, measuring several factors:

- Sound levels.

- Temperature.

- Humidity.

- Vibration.

- Lighting.

- Carbon dioxide.

Mohammadi measured sound levels in terms of weighted decibels, which takes into account both noise level and exposure duration.

During a ride with CBC News, Mohammadi measured levels around 76.6 weighted decibels on a new AZUR train, and levels a bit over 80 weighted decibels on an older Metro car.

Mohammadi gives a ride of around 80 decibels a fair rating, not good or excellent. He noted that users who are listening to headphones might be tempted to turn the volume up, which could be fatiguing and uncomfortable.

For comparison, a noise of around 80 decibels can be compared to the noise of a garbage disposal when you're standing about three feet away.

According to his observations, noise levels within the Metro are within safe levels for human hearing. Federal safe work place guidelines state the maximum safe amount of time to be exposed to a noise around 87 decibels is eight hours.

Other factors that he took into account include vibration, which he measured by recording acceleration with a smartphone​.

He then used that acceleration data to come up with a weighted average he used to determine overall rider comfort.

"Vibration is very important when you're sitting and trying to read or concentrate," he said, adding that of course lighting is another factor to riding comfort.

Overall, he says Montreal's Metro is quite warm, and he pointed out it may feel more uncomfortable in the winter because people are dressed for subfreezing exterior temperatures, not the balmy 24-26 C found inside Metro trains.

But he cautions that it is difficult to focus on one factor at the expense of others.

"Generally, we cannot actually assign priority to comfort factors. Because some people are sensitive to noise, some to...vibration," he said.

He did an online survey of over 200 Metro riders at Concordia and found a slight preference for temperature as the most important comfort factor, followed by noise, but cautioned the differences were not significant.

Newer is better

Whatever the conditions of each individual ride, Mohammadi says overall, Montrealers will have a more comfortable ride on the new AZUR trains.

The STM says it took comfort into account as the service went through the five-year process of obtaining the new trains.

From 2007 to 2012, the transit agency held focus groups and conducted surveys on the design of the interior of the cars, and communications system.

The newer AZUR cars have plenty of features meant to make riders happy, including:

- An environment that minimizes noise.

- Scratch and graffiti resistant surfaces.

- Indirect, softer lighting.

- Better suspension to minimize vibration.

- Ergonomic seating.

- Wider doors.

​However, some riders complained to the STM when the cars were first launched, complaining that grab bars weren't placed to be easily accessible to shorter people, that the ventilation was too was too strong and "pushes the air directly in the face of users facing forward" and that the new cars were too hot.