G-02 — Temporary Permission for Putting Gas Metering Devices Into Service Without Sealing

Category: Gas
Bulletin: G-02 (rev. 1)
Document: GEN-40, S-EG-05, S-EG-06
Issue Date:
Effective Date:
Supersedes: G-2-E


Table of content


1.0 Purpose

The purpose of this bulletin is to establish policy requirements for granting temporary permission to place gas metering devices into service without sealing and to clarify the types of modifications that may be made to such devices without triggering the need for reverification.

2.0 Scope

2.1 This bulletin applies to electronic pressure, temperature and supercompressibility correcting gas meters (hereafter referred to as devices). Such devices include electronic volume conversion (EVC) devices, gas flow meters with integral EVC functions, and flow computers.

2.2 This bulletin does not apply to:

  1. Devices conforming to a type approved as a configurable device in accordance with the requirements of S-EG-05 and S-EG-06 prior to .
  2. Devices conforming to a type initially approved and/or subsequently approved for modifications on or after (including previously used devices upgraded with a version of software/firmware approved on or after ).
  3. New and renewed devices verified as of , and subsequently reverified thereafter.

Note: Device types identified under section 2.1 that are submitted for initial or modification approval are subject to the requirements of Measurement Canada (MC) specifications S-EG-05 – Specifications for the Approval of Software Controlled Electricity and Gas Metering Devices and S-EG-06 – Specifications Relating to Event Loggers in Electricity and Gas Metering Devices. Approval applicants should ensure devices intended for use in service as configurable devices are in full compliance with the applicable requirements of these specifications.

3.0 Authority

In accordance with this bulletin, a temporary permission is granted under the authority of subsection 9(2) of the Electricity and Gas Inspection Act.

4.0 Terminology

Configurable device

For the purposes of this bulletin, any device that has been approved to permit legally relevant parameters to be modified by the end user or by any type of communications link from another device, such as a geographically local or remote console or computer, whether or not the secondary device is part of the network connecting the devices.

Electronic volume conversion device

A software controlled device with integral pressure and/or temperature sensors that calculates and totalizes the line volume, base or standard volume, and possibly energy of gas flowing through a single meter. These calculations are performed using approved standard algorithms with a combination of live inputs and fixed and/or user configurable parameters.

Flow computer

A software controlled device that calculates, time stamps and totalizes the mass, volume and/or energy of gas flowing through one or more metering devices. These quantities are expressed at line and/or base conditions and calculations are performed using approved standard algorithms with a combination of live inputs from other approved gas metering devices and fixed and/or user configurable parameters.

Legally relevant

Software, hardware, data or a part thereof which interferes with properties regulated by legal metrology.

Legally relevant parameter

Parameter of a measuring instrument, electronic device or a sub-assembly subject to legal control. Legally relevant parameters typically form part of the legally relevant functions performed by a device. For the purposes of this bulletin, legally relevant parameters are those parameters which are, either individually or as part of a function, subject to verification under the Electricity and Gas Inspection Act.

Verification triggering event

Any event deemed by Measurement Canada to require a verification of the device before it is permitted to be used or continued for use in trade.

5.0 Policy

5.1 Temporary Permission

Subject to the terms and conditions described in sections 5.2 and 5.3, temporary permission is hereby granted for verified or reverified devices within the scope of this bulletin to be placed into service with verification marks and seals that do not restrict access to their local and/or remote software configuration capability and/or does not prevent battery exchanges.

5.2 Application of Verification Marks and Seals to Devices Granted Temporary Permission

5.2.1 Any verified or reverified device not intended to be used in service as a configurable device shall be sealed and secured in accordance with the provisions of the Notice of Approval, with the exception of those provisions that would prevent battery exchanges. Where this exception precludes the application of all physical sealing, a verification mark shall be applied.

5.2.2 Any verified or reverified device intended to be used in service as a configurable device shall be sealed and secured in accordance with the provisions of the Notice of Approval, with the exception of those provisions that would:

  1. restrict access to their local and/or remote software configuration capability; and/or
  2. prevent battery exchanges.

Wherever this exception precludes the application of all physical sealing, a verification mark shall be applied.

5.3 Modifications to Devices Granted Temporary Permission

5.3.1 Modifications to a device's legally non-relevant and/or unapproved software parameters are permitted and are not considered to be verification triggering events.

5.3.2 Subject to 5.3.5, modifications to legally relevant parameters utilized by a verified legally relevant function are permitted and are not considered to be verification triggering events provided such parameters remain within the function's approved range.

Examples of such parameters include those utilized by the American Gas Association (AGA) and Gas Processors Association (GPA) standard algorithms (e.g. AGA3, AGA7, AGA8, NX19, GPA2172, etc.) such as gas composition, specific gravity, heating value, orifice diameter, pipe diameter, base pressure, base temperature and atmospheric pressure.

5.3.3 Subject to 5.3.5, a modification that results in the switching of one previously verified legally relevant parameter for another is permitted and is not considered to be a verification triggering event.

An example of such a parameter is the volume per revolution of an EVC device that is designed to be installed on the instrument drive of a meter.

5.3.4 Modifications to legally relevant parameters relating to integral telemetering functions that are exempt from verification and sealing pursuant to MC bulletin GEN-33 are permitted and are not considered to be verification triggering events provided the as-left settings continue to satisfy any conditions associated with the exemption.

Examples of such parameters include those associated with a device's integral pulse generators such as pulse weight, pulse signal strength and pulse width.

5.3.5 Hardware or software modifications affecting a device's performance and/or measurement accuracy are verification triggering events.

Examples of such modifications include hardware calibration adjustments and modification of type-specific parameters, calibration parameters, and parameters with hardware dependency.

5.3.6 Modifications to registered volume, mass and/or energy quantities used to form the basis of a charge are verification triggering events.

5.3.7 Unless specifically permitted in a device's Notice of Approval, all component exchanges and physical modifications to a device, with the exception of battery exchanges, are verification triggering events.

5.3.8 Updating, downgrading and/or reloading a device's software/firmware are verification triggering events.

6.0 Expiry of Temporary Permission

No date is set for the expiry of the temporary permission provided for by this bulletin. As of , all devices that continue to fall within the bulletin's scope of application will qualify to receive the temporary permission for the duration of their service life.

7.0 Revision

The purpose of this revision is to update and clarify the bulletin's scope, sealing requirements, and the types of modifications that are permitted without triggering a reverification of the device.

8.0 Additional Information

For additional information regarding this bulletin, please contact the Senior Program Officer responsible for gas measurement.

Gilles Vinet
Vice-President, Program Development Directorate
Measurement Canada