Natural gas is treated with an odorant that often smells like sulfur or rotten eggs. Other possible warning signs include a hissing or roaring sound near gas piping, blowing dirt, bubbling water, or dead vegetation above an underground line.
If you notice any of these signs, leave the area immediately and take everyone and all pets with you. Don’t turn lights or appliances on or off, use a phone inside, open the garage door, light a flame, smoke, or start a nearby vehicle. Once you are safely away from the property, call 911 and your natural gas or propane supplier. Don’t return until emergency personnel or the utility confirms that it is safe.