KITCHENER -- Grand River Transit operators are not required to wear a mask while behind the wheel of a vehicle.

Two drivers have tested positive for COVID-19 in the past week, causing concerns and questions about potential risks. One driver last worked on Oct. 4 and the other on Oct. 7.

Masks aren't mandatory when drivers are in their seats, but they are required in common areas.

"Walking to and from their vehicle, any area where they might be encountering passengers or other employees," said Neil Malcolm, assistant director of transit services with GRT.

There are Plexiglas barriers between the drivers and passengers.

Transit riders are also asked to do their part and stay distanced.

"When the bus is in motion, customers are asked to stay behind the yellow line so there is a physical separation between the employees, the operators and customers," Malcolm said.

Some people who spoke to CTV News said they'd like to see the mask policy change for drivers.

GRT said the two drivers who tested positive for COVID-19 are experiencing mild symptoms and recovering in isolation. Officials also said they're following proper contact tracing protocols.

"Anyone that was at higher risk or in close contact with them was notified," Malcolm said.

Passengers are required to wear a face covering while on board.

The union representing GRT drivers said the rules are being followed and drivers are wearing masks when needed.

"When we're safe behind the shield/barrier, a mask is not required," a statement from the union said in part.

GRT officials said they've increased cleaning and sanitizing procedures since the positive cases.

Public health officials weren't available for comment.

Anyone who is feeling sick should stay home and not take GRT vehicles. That rule also applies to staff, who do a self-assessment every day before coming to work.