Masks or face coverings are now mandatory for passengers on all GO Transit vehicles and UP Express trains.
Metrolinx announced the measure last week and said it would go into effect on Tuesday.
The transit agency said it’s the “right thing to do” for the safety of riders and transit staff.
“The wearing of face coverings is another layer of personal health safety that allows us all to cope with a gradual increase in people that will be using buses, trains and stations,” Metrolinx CEO Phil Verster said.
Metrolinx said more than half of GO Transit and UP Express riders have been wearing some sort of protective barrier over their nose and mouth.
The transit agency is asking riders to be understanding of people who are not able to wear face coverings due to pre-existing conditions.
“In terms of our enforcement, of our requirement of people to wear face coverings, we will focus on education rather than enforcement,” Verster said. “Our employees will help customers on buses and trains if they haven’t got face coverings and we will ensure that no one will be left behind.”
Metrolinx said transit staff will be on board trains, buses and at the stations to inform riders of this new requirement.
It has been mandatory for Metrolinx employees to wear a face covering across the system since May.
Earlier this month, Metrolinx installed clear plastic dividers between seats on five GO trains. It also introduced new signage and one-way entry/exit doors on some of its trains in order to limit the amount of face-to-face contact between passengers.