LONDON, ONT. -- As ridership rebounds, other cities require wearing masks on public transit, but they remain optional in London.

“I’m protecting you by wearing a mask, but you also have a responsibility to protect me. I think it should be across the board,” explains Malcolm Wood.

Wood is among a growing number of mask-wearing riders calling on the London Transit Commission (LTC) to mandate the practice for all passengers.

“A number of the buses have too many people in them. You can not social distance in any way,” Wood adds.

Other cities, including Guelph, Hamilton and Toronto now require passengers to wear masks to reduce the risk of spreading COVID-19.

In London, the Middlesex-London Health Unit (MLHU) ‘strongly recommends’ masks - but leaves the choice up to riders.

Chair of the London Transit Commission, Phil Squire wants masks made mandatory.

“I would welcome the Medical Officer of Health to issue something very clear,” says Squire. “If he says ‘I believe from a health point of view that masks are required on buses,’ it happens immediately.”

But during his daily media briefing, MLHU Medical Officer of Health Dr. Chris Mackie suggested the LTC doesn’t need his OK.

“It’s entirely open to the transit system to make that requirement of their transit users.” he said.

But Squire argues the responsibility rests with the health unit.

"Other municipalities who have ordered it, what you’ve seen is it has come from the medical officer of health, and that’s what should happen in London."

According to transit riders, mask wearing varies by route and time of day. But most estimates provided to CTV News were in the range of 20 to 25 per cent.

Darren Jackson values his freedom to choose not to wear one unless the bus is really crowded, “We’re in Canada, it should be optional, just as most businesses are doing.”

Marical Omilig says as a PSW (persona support worker), she chooses to wear a mask while riding, “For me, it’s my protection, and (for) the protection of the person next to me.”

Mackie suggests a medical order to mandate masks on buses would have to be driven by local COVID-19 data.

“The question, whether they should become mandatory or not, is largely a question of whether we are seeing disease rates continue to trend down in our community.”

Squire says requiring masks, in addition to installing new plastic shields for drivers, would let the LTC start collecting fares again.

“It’s one of the things I believe we need to a normal service, where people are entering through the front door.”

The London Transit Commission will receive another update on the impacts of the pandemic next week.