Amid a statements and warnings surrounding soaring temperatures, many Edmontonians are using air conditioned spaces to escape – but for some ETS drivers, it’s not an option.

The extreme heat is getting to some Edmonton bus drivers – on Thursday, five needed to stop work due to health issues stemming from the heat, one needed an ambulance.

CTV News has learned Edmonton is the only major city in Canada to not have air conditioning on its conventional bus fleet.

That revelation shocked a retired bus driver from Orlando, Florida – in Edmonton for a convention.

“It’s a health issue for the driver, especially because they’re up in that big bubble,” Mary Ann Taylor said. “It’s like a sauna, especially up in the driver’s seat.”

At issue, money, its estimated installing air conditioning on new $500,000 buses would cost $35,000. It would cost $50,000 per bus to retrofit existing vehicles.

The Edmonton Transit Service fleet is made up of 900 buses.

However, the City said there have been few heat-related incidents.

The union representing bus drivers is pushing the City to invest in air conditioning before heat is blamed for a more serious incident.

“It can take a tragedy to get people to more, we’re trying to forestall that tragedy by gathering the date and proving to City Council that you have a responsibility to protect people here,” Amalgamated Transit Union President Steve Bradshaw said.

The City is looking at adding AC as an option when new buses are ordered in 2017, but said drivers should be taking precautions themselves.

“They’re almost like outside workers, except they’re in a vehicle,” Linda Kadatz with ETS Operations said. “They need to take the same precautions any one of our construction workers take when they’re at work.”

With files from Dan Grummett