Firefighters attended a fire at a flat on St Nicolas Walk, Rawmarsh on Tuesday night.
A woman in her 90s had left a plastic bag on a cooker hob, causing it to ignite at around 10.45pm
Smoke alarms sounded and alerted neighbours, who contacted the fire service.
The fire was already out when crews from Dearne and Rotherham fire stations arrived on the scene, but the property was smoke logged.
Firefighters ventilated the property and the woman was taken to hospital for a precautionary check up.