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Gas Safety

Smell Gas. Act Fast.

Gas leaks can result in fires and explosions. It's important that you and your family know how to recognize a gas leak and what to do if you suspect a leak.

How to Recognize a Gas Leak

Smell—A distinctive, strong odor similar to rotten eggs
See—A white cloud, mist, fog, bubbles in standing water, blowing dust, or vegetation that appears to be dead or dying for no reason
Hear—Roaring, hissing, or whistling

What to Do If You Think There Is a Gas Leak

  • If the odor is strong, leave immediately and take others with you.
  • If you are outside, leave the area immediately.
  • Don’t light a match or smoke, turn appliances or lights on or off (including flashlights), use a telephone, or start a car. Doing so can produce sparks that might cause the gas to explode.
  • Find a phone away from the area and call 911 or 1-800-75-CONED (1-800-752-6633). You can report leaks anonymously.
  • Don’t assume someone else will report it.
  • National Grid customers should call 1-718-643-4050.
  • Follow directions from emergency responders who are on site.

Why Natural Gas Smells Like Rotten Eggs

Natural gas doesn’t actually smell like anything. That’s why a chemical called mercaptan is added to natural gas so you’ll be able to smell it in case of a leak. Mercaptan has a very distinct and unpleasant odor that many people compare to the smell of rotten eggs.

    Odor Fade

    Certain conditions or circumstances may diminish the smell of mercaptan. If you have a weak sense of smell, odor fatigue from smelling the same aromas for an extended period, or if multiple competing odors are in the area, you may not be able to detect the odorant.

    Physical or chemical processes may cause the odorant to fade to the point where it’s no longer detectable, including:

    • Adsorption, absorption, and oxidation.
    • Newly-installed metal, or sometimes plastic, piping (utility or customer).
    • Size, length, and configuration of the piping. • The presence of rust, moisture, or other substances in the pipe.
    • Gas composition, pressure, and/or flow. Intermittent, little, or no flow over an extended period of time may result in the loss of odorant until gas flow increases or becomes more frequent.
    • If a natural gas leak occurs underground, the surrounding soil may cause odor fade such that the odorant may not be detected by smell in the atmosphere.

    Con Edison provides this information solely as a service. You are responsible for working safely and understanding and complying with all applicable laws, regulations, and safety provisions when working on or near natural gas equipment. If you suspect a gas leak but can’t smell it, you should still find a phone away from the area and call 911 or 1-800-75-CONED (1-800-752-6633).

    Gas Leak FAQ

    Doing Yard Work? Call 811

    Know what’s underground before you start a project.

    • Get your underground utilities marked for free
    • Keep your home, family, and neighborhood safe
    • Prevent an emergency, property damage, or fines

    Call 811 Before You Dig

    If a digging accident occurs, call 911 and 1-800-75-CONED (1-800-752-6633)

    Safety Precautions When Working With Gas Piping

    • Do not purge the contents of a gas line into a confined space. Any purging of a gas line should be done by venting the contents to the outside atmosphere away from potential ignition sources.
    • Always use gas detection equipment (combustible gas detector) during purging operations or when otherwise working on or around gas piping systems. • Do not rely on your sense of smell alone to detect the presence of natural gas.
    • Consult the National Fuel Gas Code (NFPA, Chapter 8) and all applicable laws and regulations for additional purging requirements.
    • When installing gas appliances or equipment, the manufacturer’s instruction manual should be followed in accordance with the applicable national, state, or local codes.

    Excess Flow Valves

    Your natural gas service is safe, clean, and reliable. But if a contractor excavating on your property accidentally damages your gas pipeline, it could cause a gas leak. To avoid this, please insist that any workers (including yourself) digging around your home or business call 811 before excavating so we can make sure they’re digging safely.

    As an optional added safety measure to protect your property from a gas leak resulting from excavation damage, you can request to have an “excess flow valve” installed, at your expense, between the street and your meter. This mechanical safety device will automatically shut off the flow of gas if your service line breaks. This can reduce the risk of fire, explosion, and injury if the line is damaged, but it won’t automatically shut off the gas if there is a small leak.

    To install the valve, we must excavate the service line where it connects to the gas mainline piping that runs down your street. We will then turn off your gas, install the valve, backfill the excavation and relight your appliances. The approximate cost to install this optional feature is $4,000 for a recently installed service, or $25,000 for an older service. This cost may vary based on your location. There will be no additional costs to maintain or replace the device.

    Excess flow valves are installed only on service lines that operate at pressures of 10 psig or greater and for loads of 1,000 standard cubic feet per hour or less. Other exceptions may apply. To learn more, to find out if your gas service is eligible for this equipment, or to schedule an installation date that works for you and us, please login to Project Center and create a new request.

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