HomeMy WebLinkAbout20250108Gas Meter Testing SOP 2025.pdf AVISTA UTILITIES
GAS METER TESTING SOP-
MEASUREMENT PERFORMANCE
PROGRAM
(PMC PROGRAM)
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 1 of 13
CONTENTS
1. CONTENTS
2. SCOPE
3. GENERAL
a. COMPLIANCE
b. HISTORY
4. GAS METER MEASUREMENT PROGRAM REQUIREMENTS
a. Test of Customer Meters
b. Customer Meter Accuracy
c. Customer Meter Test Loads
d. Meter Test Procedures and Test Records
e. New Meters
f. Installed Meter Testing Program
g. Meter Test Equipment and Application
5. APPENDIX-COMPLIANCE STANDARDS
a. Idaho
b. Oregon
c. Washington
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 2 of 13
SCOPE
This procedure covers the methodology,testing requirements,and annual reporting guidelines for
Avista's gas meter measurement performance testing program(PMC Program) for new and in-service
meters.
Deviations or changes to this SOP(Standard Operating Procedure) shall be approved by the Gas
Measurement Manager. Material changes require concurrence with the governing commission. Non-
material changes shall be submitted to the commissions in conjunction with annual meter performance
statistics.
GENERAL
COMPLIANCE
It is the intent that this PMC Program is in accordance with the following rules,regulations, and
stipulations.
Idaho: Avista ID Gas Tariff Rule No. 27, Section 25,effective November 1,2018,has been approved
and prescribes the minimum inspection and testing requirements.
Oregon: Gas meter testing requirements for Avista are promulgated by Oregon Administrative Rules,
Chapter 860,Division 023 "Service Standards", Section 0015 (Testing Gas and Electric Meters). Avista
Gas Tariff Rule No. 18, Section 20,has been approved and is in compliance with the requirements of the
applicable OAR and prescribes the minimum inspection and testing requirements.Additionally,the
second Settlement Stipulation agreed to in Docket No.UG 461, Order No. 23-384 is accounted for with
respect to the Oregon meter plan.
Washington: Gas meter testing requirements for Avista are promulgated by Washington Administrative
Code, Chapter 480-90"Gas companies -operations", Section 333 (Initial accuracy of meters), Section
338 (Metering tolerance), Section 343 (Statement of meter test procedures), and Section 348 (Frequency
of periodic meter tests. Avista Gas Tariff Rule No. 170, Section 20, effective November 30, 2011,has
been approved and is in compliance with the requirements of WAC 480-90 and prescribes the minimum
inspection and testing requirements.
HISTORY
Avista's current random meter measurement performance program is in accordance with ANSI Z1.9
(Inspection by Variables). Random sampling and testing is completed for all meters 1000 cubic feet per
hour(cfh) and smaller. The program was revised and upgraded in 2009. The prior program was in
accordance with inspection standard ANSI Z 1.4 (Inspection by Attributes). The change in inspection
standard and programmatic changes were completed to enhance the quality and accuracy of the
measurement performance program.
2011: Meter Testing Program Enhancements
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 3 of 13
In 2011 the gas meter testing program was enhanced as follows:
• Random sampling program-Redefined a meter population. Previously a meter population was
defined as meters of the same model,installed in the same State jurisdiction, and purchased in the
same year. The revised definition for a meter population now includes meters of the same model,
size, and manufactured in the same year. The new definition removes the criteria to test meters by
state.A statistical analysis of meter testing results for all three(3)states revealed that the mean
accuracy and standard deviation of accuracy about the mean are similar for all three states and
that any difference is not statistically significant, indicating that state test results can be
combined. Random sampling gas meter testing requirements for 2012 were developed using the
revised meter population definition.
• Installed turbine Meters: Changes were made to expand turbine testing requirements to include
both single rotor and dual rotor auto adjust meters.
• Installed rotary meters: Changes were made to provide clarification regarding necessary test
requirements for rotary meters.
2019: Implementation of the Installation Constant Adjustment
In 2019 a new subpart titled"Meter Data Management Calibration"was added to section VI Installed
Meter Testing Program,part c. This subpart defines an alternative means to address meter families that
are experiencing a consistent deviation in mean accuracy identified by the sample meter testing program.
If a statistical analysis shows that a meter family is experiencing a consistent deviation in mean accuracy,
the meter readings of that family may be corrected by adjusting the entire family's Installation Constant
value in the Meter Data Management system rather than replacing the meter.
Avista determines a meter family's eligibility for the use of an Installation Constant adjustment by
following ANSI-ZI.9. This standard defines the acceptable standard deviation for a population of given
size and inspection status.For example, given a population size of 3,201-10,000,a tightened inspection
status calls for a sample size of at least 100 and prescribes an acceptable standard deviation of 1.26 for the
lot. Avista then compares the calculated standard deviation of the actual test results to the 1.26
recommended by the ANSI standard. If the calculated standard deviation is less than 1.26,the family is
determined to have consistent enough results to be considered for the Installation Constant adjustment. If
the calculated standard deviation is more than the acceptable value,that means the test data is more
random(not consistent); it would not fit into an acceptable bell curve, and therefore is not eligible for the
Installation Constant Adjustment.
All meters that are in the meter family will have the Installation Constant correction applied. Meter
families whose Installation Constant has been adjusted are not considered a failed family meter because
they will remain in service and will continue to be randomly pulled and tested under tightened inspection
as part of the installed meter testing program. Their Installation Constant value will be reevaluated and
adjusted every year.
2023: Oregon Tariff No. 5,Rule 18 Update
In 2023 the Oregon Gas Tariff No. 5,Rule No. 18 was updated to reflect the terms of the settlement
stipulation—docket number UG 461, Order No. 23-384. The major changes to the tariff are as follows:
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 4 of 13
• The installation constant adjustment solution described above is not approved for Oregon meters.
Meters that utilize the installation constant adjustment must be replaced no later than December,
2028.
• Meter families will begin the random testing program at 5 years of age.
• Meter families will fail after one year of non-conformance(remove the tightened sampling rule).
This SOP was updated to reflect the changes above.
2025: Addition of ultrasonic meters(USM)
As an alternative meter type,Avista plans to introduce a metering technology(subject to Commission
approval/tariff incorporation)that is new to us but not new to the industry. Ultrasonic Meters (USMs)
have no moving parts. They contain electronic components that measure pressure,temperature, and the
speed of the gas to determine the flowrate.
For small capacity(<5001 cfh),Avista is involved with an effort led by the American Gas Association to
create meter proving standards for residential/commercial sized USMs. We plan to use the results of that
effort to drive the meter testing protocol that we adopt.
For large capacity(>5000 cfh),Avista has decided to rely on annual diagnostic tests performed by the
meter itself to ensure accurate measurements. Also,these meters perform diagnostic tests at regular
intervals and will send an alarm signal if the test does not pass. If this happens, an Avista technician will
be dispatched to the site to troubleshoot the issue. This protocol is based on the manufacturer's
recommendations and our review of how peer utilities test this type of meter.Additionally, like turbine
meters,these meters will be tested with a transfer prover or at an approved offsite facility at a maximum
interval of every ten(10)years.
GAS METER MEASUREMENT PROGRAM REQUIREMENTS
I. Tests of Customer Meters
a. Avista shall maintain a quality control program to verify performance accuracy of new
meters and installed meters.
b. Testing of Small Cgpacitv Meters. All meters with capacities up to and including one
thousand(1,000)cubic feet per hour(cfh) at ''/z"differential pressure that have been in
service for:
i. Washington and Idaho meters: Ten(10) or more years, and
ii. Oregon meters: Five(5) or more years
as established by either the last install date or manufacture date shall be tested through
annual random sampling using sample size methods in accordance with ANSUASQ-Z1.9
or other generally accepted statistical method that conforms to the requirements of the
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 5 of 13
applicable sections of ANSI B.109.1 and B 109.2 measuring in-service performance of
diaphragm type gas meters.
c. Testingof f Larger Capacity Meters. All meters with capacities greater than one thousand
(1,000)cfh that have been in service for:
i. Washington and Idaho meters: Ten(10) or more years,and
ii. Oregon meters: Five(5) or more years
as established by either last install or manufacture date shall be replaced or field tested
based on a periodic schedule. Diaphragm type meters shall be tested in accordance with
applicable sections of ANSI B 109.1 and B 109.2. Rotary type meters shall be tested in
accordance with applicable sections of ANSI B 109.3.
d. Testing frequency:
Diaphragm, 250-1000 cfh Statistical sampling
Diaphragm, between 1001 and 3000 cfh (WA/ID) Every 10 years
Diaphragm, between 1001 and 3000 cfh (OR) Every 5 years
Diaphragm, 3001 and greater cfh Every 5 years
Rotary, all sizes Differential test Every 5 years
Turbine, all sizes Spin test annually and proof
tested every 10 years
Ultrasonic, small capacity TBD
Ultrasonic, large capacity(not residential/commercial) Annual diagnostic test
11. Customer Meter Accuracy
a. Accuracy of Meters
i. Diaphragm Meters:
1. A new gas meter installed for the use of any customer shall not be more
than one (1)percent slow or fast.
2. Every meter removed from service and opened for repair shall have the
meter tolerance adjusted to 100%plus or minus 0.5%,with no greater
spread than 0.7%between the check and open prior to being reinstalled.
3. Meters not opened for repairs may be reinstalled without adjustment if
found to be not more than two(2)percent in error slow or fast,per
Section III(Customer Meter Test Loads).
ii. Rotary Meters
1. A new gas meter installed for the use of any customer shall not be more
than one(1)percent slow or fast.
2. Meters inspected by differential pressure testing shall confirm that the
meter is performing within 150% of the manufacturer's specification for
differential pressure at the operating pressure.
3. Every meter tested by proving shall be adjusted to be not more than two
(2)percent slow or fast before being reinstalled.
Hi. Turbine Meters
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 6 of 13
1. A new gas meter installed for the use of any customer shall not be more
than one (1)percent slow or fast.
2. Meters inspected by spin testing shall confirm that the meter is
performing within the manufacture's limits.
3. Every meter tested by proving shall be adjusted to be not more than two
(2)percent slow or fast before being reinstalled.
iv. Ultrasonic Meters
1. A new gas meter installed for the use of any customer shall not be more
than one(1)percent slow or fast.
2. Every meter tested by proving shall be adjusted to be not more than two
(2)percent slow or fast before being reinstalled.
b. Removal of Defective Meters from Service.No meter that is mechanically defective shall
be placed in service or allowed to remain in service after the defect has been discovered.
When any gas meter is not connected and in service,the inlet and outlet will be capped to
prevent the drying out of diaphragms and contamination of the meter with dirt and debris.
The exception shall be when stored indoors during the testing and/or repair process.
TII. Customer Meter Test Loads
a. Testing of Meters,Test Equipment.All tests to determine the accuracy of registrations of
gas service meters shall be made with a suitable meter prover or testing equipment as
detailed in this standard.
b. Gas Flows During Testing. The flow rate to be used in testing meters,except high
volume meters with capacity in excess of test equipment capability,will be at twenty(20)
percent(Check) and one hundred(100)percent(Open)of their capacity. For the purpose
of determining the accuracy of these meters,the average of the two results shall be used.
c. High Volume Meters. Turbine,rotary, and ultrasonic meters that have rated capacities in
excess of the mechanical limits of the proving equipment shall be tested at a minimum of
two (2)points of flow with each at or above a minimum of 15%of the rated capacity of
the meter. For purposes of the test the two results shall be averaged and shall conform to
the standards set forth in Section II(Customer Meter Accuracy).
IV. Meter Test Procedures and Test Records
a. Reporting
i. After December 31 of each year,meter test results will be summarized,
analyzed and forwarded to all the three State Utility Commissions. Retention
and filing of records will be in accordance with the appropriate Commission
requirements.
b. Test Records
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 7 of 13
i. After December 31 of each year,meter test results will be analyzed and
summarized. Annual results of all meter accuracy tests will be tabulated and
retained in accordance with the appropriate Commission as follows:
1. Idaho: Avista ID Gas Rule No. 27, Schedule 170, Section 25
2. Oregon: OAR 860-023-0015(4)
3. Washington: WAC 480-90-353
ii. Avista shall keep records of tests of the accuracy of each of its meters,which
may be superseded by a later test,but shall be maintained for not less than two
years. These records shall give:
1. sufficient information to identify the meter,
2. the reason for the test,
3. the date of the test and reading of the meter,
4. an identification of the person making the test,and
5. accuracy, as found and as left,together with enough of the data taken at
the time of the test to permit the convenient checking of the methods
employed and the calculations.
c. Technical Standard. Technical performance requirements for diaphragm natural gas
meters shall be per the current versions of ANSI B 109.1 and ANSI B 109.2. Technical
performance requirements for rotary type natural gas meters shall be per the current
versions of ANSI B109.3.
d. Uniquely Defective Test. An individual meter test result within a random sample of
more than 10%error shall be declared a uniquely defective test and disregarded. A
substitute test will be made with meter selected from within the same test family. Subject
meter shall be adjusted or replaced.
V. New Meters
a. New meters shall be factory tested and certified to meet accuracy criteria specified by
Section 11(Customer Meter Accuracy).
i. Manufacturers shall provide results of new meter testing that conforms to
generally accepted practice for meter accuracy and performance. Diaphragm
meters shall meet the standards set forth in ANSI B109.1 and ANSI B.109.2.
Rotary meters shall meet the standards set forth in ANSI B 109.3.
b. Inspection and acceptance testing by Avista prior to installation of new meters.
i. Each meter shipment will be inspected for physical damage. Meters found to
be damaged or in damaged packaging will be tested,repaired and/or calibrated
or returned to the manufacturer as described herein.
ii. Normal acceptance testing described herein,not associated with physical
damage found on arrival of the shipment,will be performed for all meters not
factory tested prior to shipment. Expanded testing beyond normal test
quantities for shipments found to be non-conforming through acceptance
testing will be paid for by the manufacturer or the shipment returned to the
manufacturer per negotiations between Avista and the manufacturer.
GAS METER SHOP-STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 8 of 13
c. New diaphragm type meters, less than or equal to 1000 cfh:
i. The methodology for the random sampling of new meters is derived from
ANSI/ASQ Z1.9 or other generally accepted statistical method that conforms to
the requirements of the applicable sections of ANSI B.109.1 and B 109.2.
1. The lot size to determine random sample quantity shall be the size of the
shipment.
2. Acceptable Quality Limit(AQL) for analysis of new meters will equal
1.5.
3. Normal inspection is the default inspection level.
4. Random sampling per the Standard shall be discontinued if five(5)
consecutive lots are not accepted. Acceptance procedures as detailed
herein shall not be resumed until corrective action has been taken.
d. New diaphragm meters, greater than 1000 cfh.
i. New large capacity diaphragm meters shall be tested against metering tolerance
of Section 11.
ii. Meters found to be outside of tolerance shall be adjusted per section 11. If the
meter cannot be adjusted within these standards,it shall be returned to the
manufacturer.
e. New rotary meters.
i. Rotary meters shall meet the accuracy requirements as specified in Section 11
and appropriate requirements of ANSI B 109.3.
f. New turbine meters.
i. New turbine meters shall meet the accuracy requirements as specified in
Section 11 and shall be spin tested at installation to verify they will operate
within the accuracy limits as specified by the manufacture.
g. New ultrasonic meters
i. Ultrasonic meters shall have a diagnostic test performed when installing the
meter.
VI. Installed Meter Testing Program
a. General: Meters shall be inspected and tested against metering tolerance prescribed in
Section 11. Meters found to be outside the tolerances shall be immediately adjusted or
replaced.
b. Age: For Washington and Idaho meters,testing requirements are applicable to meters that
are ten(10)years old or older. The first year of required testing is calculated as
Manufacturing year+9. For Oregon meters,testing requirements are applicable to meters
that are five(5)years old or older. The first year of required testing is calculated as
Manufacturing year+4.
c. Installed diaphragm type meters, 1000 cfh and smaller,randomly sampled: Annually,a
random sample of meters shall be selected,tested against tolerances prescribed by
Section 11, and analysis conducted using ANSI/ASQ Z1.9 (hereafter may be referred to as
the Standard). The methodology for sample sizes and analysis for the meter testing
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 9 of 13
program is derived from the Standard or other generally accepted statistical method that
conforms to the requirements of the applicable sections of ANSI B.109.1 and B 109.2
measuring in-service performance of gas meters.
i. The lot size to determine random sample quantity shall be the size of the meter
population. A meter population is defined as meters of the same model,size,
and manufactured year.
1. Meter population is synonymous with the term lot as used in the
Standard.
2. Major design changes to a meter model within a single year shall be a
new population for sampling.
ii. All the meters within a population will be identified by a"flag"in Avista's
Service Suite mobile application at the beginning of a calendar year. Meters
shall be chosen at random and in sufficient quantities to meet the guidelines for
sampling as detailed in the standard. Once the required number of meters in
each family is removed for testing the"flag"will be eliminated in Service Suite
indicating that no more meters in that family are required for testing. Meter
populations of 50 or fewer units are subject to modified sample size. Sample
quantity shall be set to avoid repeat testing of a meter more than once every ten
years.
iii. Inspection Levels, Sample Size and Test result analysis:
1. General: Analysis of population sample results shall conform to the
guidelines contained in the Standard. Acceptable Quality Limit(AQL)
for analysis will equal 10.0.
2. Normal inspection is the default level of inspection.
3. Inspection levels for meter types with five(5)year test histories are
eligible for application of switching rules.
4. Switching
a. Normal to tightened(only applicable in Washington and Idaho):
Switching rules for transition from normal to tightened
inspection shall be applied if two(2)lots out of five(5)
consecutive lots have been rejected. Oregon meters are not
authorized to switch from normal to tightened inspection.
b. Tightened to Normal(only applicable to Washington and Idaho
meters): Switching rules for transition from tightened to normal
inspection may be applied when testing has been at the tightened
level and five(5)consecutive batches have been acceptable.
c. Normal to Reduced: Switching rules for transition from normal
to reduced inspection may be applied if:
i. Preceding ten(10) lots have been on normal inspection
and none have been rejected.
d. Reduced to Normal(only applicable to Washington and Idaho
meters,in Oregon a meter family becomes a failed family if one
batch is rejected). Switching rules for transition from reduced to
normal shall be applied if one batch is rejected.
GAS METER SHOP-STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 10 of 13
5. Failure of meter population. A meter population shall be declared
defective(failed)when:
a. For Washington and Idaho meters: Three (3)consecutive yearly
inspections for a population under tightened inspection are not
accepted based on AQL of 10.0 for overall performance (double
specification limit)AND/OR
b. For Washington and Idaho meters: Two(2)consecutive yearly
inspections for a population under tightened inspection are not
accepted based on AQL of 10.0 for overall performance (single
specification limit)which measures meters running fast, also
referred to as Failed Fast.
c. For Oregon meters: One(1) annual inspection for a population
under normal or reduced inspection is not accepted based on
AQL of 10.0 for overall performance.
These failed meter families shall be removed from service as described
by subpart 6 below.Alternatively, in Washington and Idaho only,
qualifying meters may have their Installation Constant updated in the
Meter Data Management system as described in subpart 7 below.
6. Removal of failed meter population: Removal of a meter population of
less than 2500 units may take place within one(1)year. Removal of
meter population of more than 2500 units may take place over two(2)
years. Removal of meter population of more than 5000 units may take
place over three(3)years. Removal of meter population of more than
7500 units may take place over four(4)years.
7. Meter Data Management calibration(a0licable to Washington and
Idaho meters only): If a statistical analysis shows that a meter family is
experiencing a consistent deviation in mean accuracy,the meter reading
may be corrected by adjusting the entire family's Installation Constant
value in the Meter Data Management system rather than replacing the
meter. For a meter family to qualify for the Installation Constant
adjustment,the actual standard deviation of the meters pulled and tested
must be less than the acceptable standard deviation determined by ANSI
Z1.9. Meter families whose Installation Constant has been adjusted are
not considered a failed family meter because they will remain in service
and will continue to be randomly pulled and tested under tightened
inspection as part of the installed meter testing program. Their
Installation Constant value will be reevaluated every year. Meters in
Oregon are not authorized for this method of adjustment.
d. Installed diaphragm meters, greater than 1000 cfh,periodic test.
i. 1001 cfh through 3000 cfh: Inspected and proved every:
1. ten(10)years or sooner for Washington and Idaho,and
2. five(5)years or sooner for Oregon.
ii. Larger than 3000 cfh: Inspected and proved every five(5)years or sooner.
iii. All meters shall be tested against metering tolerance of Section 11.
GAS METER SHOP-STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 11 of 13
iv. Meters found to be outside of tolerance shall be adjusted to within the
tolerances as specified in Section II.
e. Installed rotary meters,periodic test.
i. Testing of rotary meters will be done using either a portable transfer prover or
differential testing device.A differential test shall confirm a minimum of two
(2)points. Results of a differential test or prover test shall show that the meter
is performing within the accuracy as detail in Section 11.
ii. Meters shall be inspected and tested every five(5)years or sooner.
iii. Meters found to be outside of tolerance shall be adjusted to within the
tolerances as specified in Section II or removed from service.
f. Installed turbine meters,periodic test.
i. Single rotor turbine meters shall be inspected and spin tested annually and
determined to be within the manufacture's acceptability limits. Turbine meters
failing the spin test shall be removed from the field and repaired prior to any
subsequent installation.
ii. Auto adjust meters shall be inspected annually and determined to be operating
within the manufacture's acceptability limits. Meter Delta A(AA),the
difference between the main and sensing rotor pulses,that exceed the
manufactures recommended operating parameters shall be repaired or replaced.
iii. All turbine meters will be tested with a transfer prover or at an approved offsite
facility at a maximum interval of every ten(10)years. Tested meters shall
meet or exceed the meter accuracy requirements of Section 11.
g. Installed ultrasonic meters,less than 5001 cfh, To Be Determined.
h. Installed ultrasonic meters,greater than 5000 cfh,periodic test:
i. Meters shall have a diagnostic test performed annually.
ii. Meters will be tested with a transfer prover or at an approved offsite facility at
a maximum interval of every ten(10)years.
VII. Meter Test Equipment and Application
a. Meter test equipment
i. Transfer Prover. The accuracy of the testing equipment is ascertained through:
1. Monthly, in-house self-testing procedures.
2. Sending of Standard Meter Module to the manufacturer for periodic
calibration. The period between factory calibrations shall not exceed
five(5)years.
ii. Sonic Nozzle Prover and Bell Prover.
1. The accuracy of the testing equipment is ascertained through an
automatic test diagnostic. The diagnostic is completed each time the
prover is powered on.
2. The test equipment shall be factory calibrated every two(2)years.
b. Meters shall be tested on either: Sonic Nozzle,Bell Prover,Transfer Prover, or at an
approved offsite facility.
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 12 of 13
APPENDIX—COMPLIANCE STANDARDS
Idaho:
• Avista ID Gas Tariff Rule No. 27, Schedule 170, Section 25
• IDAPA 31.31.01 Section 154
Oregon:
• Avista OR Gas Tariff No. 5,Rule No. 18
• OAR 860-023 (Public Utility Commission)
• Sec. 16.iv. of the Second Settlement Stipulation agreed to in Docket No. UG 461, Order No.23-384
Washington:
• Avista WA Gas Tariff Rule No. 29, Schedule 170, Sections 23 and 24
• WAC 480-90"Gas companies-operations", Section 333, 338, 343, &348
GAS METER SHOP—STANDARD OPERATING PROCEDURE
Title: Gas Meter Measurement Performance Program Date: 1-3-2025
Jurisdiction: Idaho, Oregon, Washington Manager: Jeff Webb Page: 13 of 13