Triple zero received 58 calls about children left in hot cars across the Geelong region in the 12 months to 31 August, Ambulance Victoria figures show.
The figures were released as Ambulance Victoria reported a big jump in triple zero calls about the issue.
The figures prompted a warning from Ambulance Victoria for people not to gamble with their children’s lives.
Emergency management director Paul Holman said a 23 per cent increase in calls and 1433 children aged under 13 locked in cars had frustrated paramedics.
Another 100 calls reported someone older or a pet locked in a car.
Children aged under four made up 88 per cent of calls, while the number of babies aged under 12 months locked in a car increased almost 50 per cent.
Nearly half the calls were between December and March.
Mr Holman said it was clear that leaving children in a car could prove deadly yet people seemed unable to understand the risks.
“It doesn’t matter whether you accidentally lock the keys in the car with your child or make a deliberate decision to leave the child in the car. The risks are the same.
“Young children can’t regulate their body temperature like we can. That puts them at significant risk and being left in a car can quickly become life threatening.”
Ambulance Victoria tests found that even on a 29C day the inside of a car could reach 44C within 10 minutes and hit 60C in 20.
“You wouldn’t go shopping and then leave a tub of ice cream in the back seat of the car so why would you leave your children there,” Mr Holman said.