Excess Flow Valves are underground safety devices installed on some underground service lines that can stop the flow of natural gas if the line gets cut or breaks underground. ING began installing excess flow valves on new services for single family homes in 2007. If your home is older than that, or your gas service is for a commercial building or multi-family residence, you probably do not have an excess flow valve installed. Indiana Natural Gas can install excess flow valves on older and larger services. If you are interested, contact us to set up a consultation on where it might be installed for your service line and a quote on the cost, which may range between $500 and $3000.