Excess Flow Valve Notification
Federal regulations at 49 C.F.R. §192.383(d) regarding gas pipeline safety requires Northern Utilities, Inc. (Unitil) to notify customers of their right to request installation of an Excess Flow Valve (EFV) on their existing gas service line under certain circumstances. An EFV is a mechanical safety device installed inside a gas service line between the gas main in the street and the gas meter. The EFV is designed to minimize the flow of natural gas in the event of a service line break. A potential benefit is, in the event that an excavator accidentally digs up the gas service line, the valve would operate to minimize or shut off the flow of gas.
If the customer’s service line operates at a pressure of less than 10 pounds per square inch gauge throughout the year, the customer’s service line is exempt from EFV installation. An exemption will also apply if: a customer’s load exceeds 1,000 standard cubic feet per hour; the operator has experience with contaminants in the gas stream that could interfere with the EFV’s operation or cause loss of service to a customer; there is a potential for interference with necessary operation or maintenance activities, such as blowing liquids from the line; or an EFV meeting the performance standards in federal rules (§192.381) is not commercially available to the operator.
EFV Conditions & Information
EFVs do not operate on all gas service lines and certain parameters may exist where installation of an EFV is not warranted. Many customers already have an EFV installed on their existing service line.
To install the excess flow valve, Unitil will excavate the service line at its connection to the gas mainline piping that runs along the street. Unitil will then turn off the customer’s gas service line, install the excess flow valve, backfill the excavation and relight the customer’s appliances. Typically, within a few weeks a restoration contractor will return to restore the customer’s property. Under certain conditions, Unitil may need to replace the entire gas service at no additional cost.
The cost of installing the EFV is estimated to range between $2,000 -$4,000 depending on specific circumstances. Installations will be scheduled to align with other upcoming work or as soon as practicable where mutually agreeable to the customer. When scheduled at a mutually agreeable time selected by Unitil, the cost will be covered by the Company. The cost of installation may be at the expense of the customer if requested to be scheduled on an expedited basis. Individual estimates will be provided upon request.
To inquire about having an EFV installed on your gas service line, call our customer service center:
- For Maine Gas customers: 866-933-3821
- For New Hampshire Gas customers: 866-933-3820