Houston, TX – Two Houston firefighters were treated Thursday evening after they were exposed to carbon monoxide in the ambulance they were driving.

An ambulance crew from Fire Station 28 responded to help treat the firefighters, who were from Fire Station 3 in the River Oaks-Greenway area.

The Firefighters Association says they started feeling nauseous and were taken to Memorial Hermann Hospital to be evaluated.

High levels of carbon monoxide were found in the cabin of their ambulance.

In 2017 Houston firefighters raised awareness of the risks they face because of aging equipment.