Upper Darby fire investigators said deteriorated ventilation equipment caused the CO leak that sent a woman and two children to the hospital on Saturday night.
In an information release on social media, the Upper Darby Fire Department said a woman and two children were found unresponsive following carbon monoxide leak in a house in the 200 block of Kingston Road.
The call initially was reported as a medical emergency with STAT ambulance and police responding.
Officers and medics arrived to find a strong odor of gas and they requested the fire department was requested with breathing apparatus. Fire personnel entered the residence using self-contained breathing apparatus and gas detectors and found the three victims as well as carbon monoxide levels in excess of 1400 parts per million.
The victims were taken to city hospitals by STAT ambulance with assistance from Yeadon and Clifton Heights Fire Company ambulances and are expected to recover, officials said. Several other people inside the home were able to get out on their own.
Firefighters checked adjoining row homes, ventilated the home and secured the gas.
The cause of the leak was determined to be a deteriorating chimney flue cap.
Fire officials remind residents that all heaters and gas appliances should be serviced regularly by reputable companies to prevent such an issue.
The department also urged residents to install and test carbon monoxide alarms at least once a month.
CO is called an “invisible killer” because it is a colorless, odorless poisonous gas. Breathing in CO at high levels can be fatal.