Southern California Gas Co. confirmed a gas leak around 5 p.m. Monday at its Aliso Canyon facility in Porter Ranch, following reports from residents that they could small natural gas.

SoCal Gas stated the leak did not pose any health risk.

The leak was due to a gasket that failed during a routine operation to pressurize equipment after maintenance. The SoCal gas facility notified residents 90 minutes after the leak was shut off.

“The release did not present a health or safety risk to the community. The highest reading on the fence-line monitors was approximately 66 parts per million. Since the release was stopped, those readings have returned to normal levels,” SoCal Gas said in a statement.

But Northridge resident Andrew Krowne, who developed a cellphone application for residents who live within 18 miles of the facility to report any health issues, said 34 people reported symptoms including nosebleeds, headaches and burning of the throat and eyes, according to the Los Angeles Daily News.

SoCal Gas did not specify how much gas was leaked, but only the highest reading measurement during the time of the leak.