An online map that promises to make air quality readings more relatable says living in Toronto is like smoking nine cigarettes a year.

Share My Air, an interactive graphic that covers North America, not only converts air quality into the number of cigarettes smoked, it also translates the data into hours spent in a car with a smoker and time spent living with a smoker.

As of noon on Friday, the observed air pollution exposure for the past 24 hours in Toronto was equal to spending 43 minutes in a car with a smoker or living with a smoker for five months.

A graphic shows the air quality in Toronto on Sept. 4, 2015. Image via Share My Air.

In Chicago, a city of similar size, the observed air pollution exposure was equal to spending 38 minutes in a car with a smoker, living with a smoker for four months, or smoking eight cigarettes a year.

A graphic shows the air quality in Chicago on Sept. 4, 2015. Image via Share My Air.

New York City, meanwhile, had air pollution equal to spending one hour and 16 minutes in a car with a smoker, living with a smoker for six months, or smoking 16 cigarettes.

A graphic shows the air quality in New York City on Sept. 4, 2015. Image via Share My Air.

However, CityNews meteorologist Adam Stiles warned, looking at short-term data can be misleading.

“For example, seeing nine cigarettes a year on an air quality day like today, would mean the air quality would have to be the same everyday, year round,” Stiles said.

“Looking at it on the full year probably would make the numbers more believable as air quality significantly improves during the winter months on the whole. Basically, don’t get too wrapped up in the daily, weekly, or monthly numbers,” he said.

The program takes data from the EPA Air Now database. Environment Canada publishes its own air quality data on a sliding, coloured scale. Friday’s reading is below:

Environment Canada publishes its air quality index in a sliding scale. Image via Government of Canada.

What do you find easier to read? Let us know in the comments.