Excess Flow Valve

Since April 14, 2017, Texas Gas Service 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.

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 uncontrolled release of natural gas by automatically closing if the service line is completely severed or severely damaged. These uncontrolled release events are primarily the result of excavation damage to service lines that occurs between the gas main and the customer's residence or building.

EFVs have been installed as required by federal regulation 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. You may read some frequently asked questions here to learn more.

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 Texas Gas Service 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.

Requesting Installation

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.


To report a natural gas odor or emergency, leave the area immediately and then call 911 and 800-959-5325.