ANSI B109 Family of Standards

For Gas Displacement Meters and Service Regulators

The AGA / ANSI B109 Committee oversees the development and maintenance four separate standards:

  • B109.1 Diaphragm-Type Gas Displacement Meters (Under 500 Cubic Feet Per Hour Capacity)
  • B109.2 Diaphragm-Type Gas Displacement Meters (500 Cubic Feet Per Hour Capacity and Over)
  • B109.3 Rotary-Type Gas Displacement Meters
  • B109.4 Self-Operated Diaphragm-Type Natural Gas Service Regulators for Nominal Pipe Size 1-1/4 Inches (32 mm) and Smaller with Outlet Pressures of 2 psi (13.8 kPa) and Less


Purchase a copy of each standard in the AGA Publication Store.

View the latest B109 Committee Roster.

Please contact Luis Escobar at if you are interested in becoming a member or observer of ANSI B109, or if you would like to be part of the review process for any of the standards above.


  • B109 Committee Fall 2021 Meeting. The committee will meet virtually on Wednesday, September 29, 2021 from 1:00 - 4:00 pm Eastern Time. The Agenda is posted here. The meeting is open to all.
  • ANSI Public Review: B109.4 Standard (closed). The Revision Draft of the B109.4 Standard (Self-Operated Diaphragm-Type Natural Gas Service Regulator for nominal pipe size 1-1/4 inches and smaller with outlet pressures of 2 psi and less) is available for review and comment. Public comments are due to by August 23, 2021 and must be submitted on this Public Comment Form. No public comments were received.
  • B109 Committee Spring 2021 Meeting. The committee met virtually on Thursday, June 3, 2021 from 1:00 - 4:00 pm Eastern Time. The Agenda is available here; connection infor is located at the top of the first page. The meeting is open to all. For more information see the Draft Minutes.
  • B109 Committee Fall 2020 Meeting. The committee met virtually on Thursday, November 5, 2020 from 1:00 - 4:00 pm Eastern Time. Meeting minutes available here (approved at Spring 2021 meeting on June 3, 2021). The committee will vote to approve these Draft Minutes at its Spring 2021 meeting, date TBD. Please check back here for a date.
  • [CLOSED] Nominations For Open Committee Positions. We are soliciting nominations to fill two open positions in the User interest category (gas utilities, consumers, gas transmission companies). If you are interested in joining the B109 Committee, please contact Luis Romeo Esobar, B109 Committee Secretariat, at Nominations are due by December 11, 2020.
  • New Standards Project. AGA submitted a Project Initiation Notification (PINS) to ANSI for the development of a new standard: BSR B109.5-202x, Self-Operated Diaphragm-Type Natural Gas Service Regulators for Nominal Pipe Size Up To 2 Inches (50.8 mm). Directly and materially affected interests wishing to receive more information or to submit comments must contact Luis Escobar ( by June 26, 2020. Read the announcement in the May 29, 2020 edition of the ANSI Standards Action
  • Revised B109 Committee Procedures. In May 2020, the committee updated our patent policy to bring it into alignment with the latest version of the ANSI Essential Requirements. Read the ANSI B109 Procedures here.

Submitting General Comments:

The ANSI B109 Standards are under continuous maintenance therefore each standard is always open for comment. Comments may be submitted via email to Luis Escobar at Comments must include:

  • Your name
  • Company name and location
  • Pertinent page and section
  • Comment and/or proposed change

History of the Development of ANSI B109:

  • 1967 (January) – Project scope approved by ANSI Mechanical Standards Board
  • 1967 (November) – Organizational meeting of ANSI Committee B109
  • 1973 (November) – First edition of B109.1 Standard approved by ANSI
  • 1980 (April) – First editions of B109.2 and B109.3 Standards approved by ANSI, as well as addenda to B109.1-1973
  • 1987 – Second editions of B109.1, B109.2, and B109.3 approved by ANSI
  • 1990 (April) – Revised committee scope approved by ANSI, now includes standard coverage for gas service regulators
  • 1992 – Third editions of B109.1, B109.2, and B109.3 Standards approved by ANSI
  • 1998 (April) – First edition of B109.4 approved by ANSI
  • 2008 (April) – Reaffirmation of B109.1, B109.2, B109.3 and B109.4 approved by ANSI
  • 2016 (December) – Second edition of B109.4 approved by ANSI
  • 2019 (February) – revised B109.3 approved by ANSI
  • 2019 (April) – revised B109.1 approved by ANSI
  • 2020 (March) – revised B109.2 approved by ANSI
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