In 2003, the Clean Roads to Clean Air Program (CRCA) was initiated by Transportation Services’ Operational Planning and Policy Unit and Toronto Environment Office’ Air Quality Improvements Branch.

Through a number of air quality studies and tests, a standard process, along with efficiency criteria were developed and used to evaluate various street sweeper technologies. Specifically, the technologies were evaluated on their efficiency in removing fine particulate matter (PM10 and PM2.5 – both considered toxic substances under the Canadian Environmental Protection Act) from roads, the concentration levels of fine particulate matter entrained into the air while sweeping, and their ability to operate year-round effectively, including during winter periods, and under various sweeping conditions typically encountered in Toronto.