Monthly Must-Knows: Excess Flow Valves

Post Date:03/06/2017 10:24 AM

As part of Mesa’s commitment to providing customers with safe, reliable energy, we strive at meeting or exceeding all federal and state requirements for safe pipeline operations and maintenance. 

As an additional safety measure, an Excess Flow Valve (EFV) may be installed on your gas line.  EFVs have been installed on new/renewed residential gas service lines since 2008 and are designed to greatly reduce the flow of escaping gas in the event a line is damaged.

If damage to a natural gas line results in gas escaping, leave the area immediately and call 911 and 480-644-4277 (GASS).

What is an EFV? 

An EFV is a mechanical safety device installed in conjunction with the City's gas service line.  In the event of damage to the City's gas service line between the street and your meter, the EFV will "trip," minimizing the flow of gas through the service line and reducing the amount of gas vented to the atmosphere.

There will be a negligible amount of blowing gas to identify that a line has been damaged, typically enough to produce a gas odor.  To report a damaged service line or if you smell gas (rotten eggs) in or outside your home, call 480-644-4277 (GASS). For more information on EFV’s visit our website at

Return to full list >>