Methane is non-toxic and creates no hazard when inhaled in limited quantities; however, if large quantities of natural gas or methane is allowed to displace air, lack of oxygen may result in suffocation.
Methane can be flammable when mixed with air between certain concentrations (4.5 percent to 15 percent) and where there is an ignition source.
SoCalGas® conducts extensive safety programs to prevent the escape of natural gas from its system; and as a health and safety precaution, adds a distinctive odor to natural gas so most people can easily notice its presence.
If you smell a natural gas odor, hear the hissing sound of gas escaping or see other signs of a leak, REMAIN calm. DON'T smoke or light a match, candle or other flame. DON'T turn electrical appliances or lights on or off, operate machinery, or use any device that could create a spark. IMMEDIATELY EVACUATE the area, and from a safe location, call SoCalGas at 1-800-427-2200, or call 911 if the damage results in a natural gas leak that may endanger life or cause bodily harm or property damage.
Further information is available on our How to Recognize and Respond to a Natural Gas Leak page.