If it feels like you're cooking on your daily commute, it's because you are.
Sydney commuters are being forced to travel inside non-airconditioned trains, with changes to the rail network resulting in older trains being pulled back into service.
The metal carriages are resulting in temperatures of more than 48C inside, according to a 9 News investigation.
These older trains were first rolled out in the 1970s.
Passengers on the Bankstown, East Hills, Airport & South and Inner West & Leppington lines have been receiving the brunt of the older trains under the new timetable.
"The train acts like a barbecue and if you're on the inside you're getting cooked," Regional manager of Flir Systems Sean Towner said of the S-set trains after taking thermal imaging temperature recordings.
"I was sweating profusely.
"I wouldn't want to be travelling on those trains, especially as our summers are getting hotter."