Excess Flow Valves

Requesting an Excess Flow Valve

Since 2017, Oklahoma Natural Gas has notified existing residential or small commercial natural gas customers of their option to request the installation of an excess flow valve (EFV) on their existing service lines as required by federal regulation.

What is an Excess Flow Valve (EFV)?

An EFV is a safety device installed below ground inside the natural gas service line between the main and meter. It is designed to restrict the uncontrolled release of natural gas by automatically closing if the service line is completely severed or severely damaged. These uncontrolled release events primarily result from of excavation damage to service lines that occurs between the gas main and the customer's residence or building.

EFVs have been installed as federal regulation requires on new or replaced single-family residential service lines since February 1998. Services installed prior to February 1998 may have an EFV due to construction maintenance activities or as a result of pilot programs in Oklahoma, Kansas and Texas.

Most residential and small commercial customers are eligible to have an EFV installed, if their natural gas system meets certain criteria including:

  • Operates at a continuous pressure greater than 10 pounds per square inch gauge (psig); and
  • Has no history of contaminants, such as liquids or debris in the natural gas system.
Details or specific questions about your eligibility may be addressed with our customer service team, if you request an EFV.

Requesting Installation

What to know

If you choose to request installation of an EFV, you will be responsible for a portion of the installation costs. You may inquire about additional information through the Contact Us section of our website. Customers will be scheduled at a time that is mutually agreeable to the company and the customer.

Questions? Contact us

Please note: EFVs are not designed to protect against an appliance or other leak in your home or business, meter leaks or partial damage to your service line. You are not required to have an EFV installed, and Oklahoma Natural Gas will install one in the future at no cost to you when, during the normal course of business, any eligible service line is replaced or the service tap connection is exposed.