Pattern approval instrument testing and assessment

The National Measurement Institute (NMI) assess your submitted pattern to ensure it can pass certain requirements and performance tests.

Find out how to apply for pattern approval.

Initial assessment

We carry out an initial assessment to see if we have all the relevant information and a suitable instrument to assess.

We usually need you to send the instrument to us but can visit you on site to inspect large instruments. We will provide details of how to send in your instrument after you apply.

Once we conduct the preliminary assessment, we provide an outline of the testing needed and a cost estimate, if required. 

You will need to:

• provide any extra information we’ve requested
• make any necessary modifications to the instrument we’ve requested

Full assessment

Once we receive the requested extra information and you have made any modifications to the equipment, we can conduct a full assessment of your pattern.

When we examine instruments for pattern approval, we assess:

• your instrument’s documentation
• how your instrument operates against the pattern approval requirements 
• the results of your instrument’s performance testing

Performance testing

Performance testing ensures your instrument:

• is accurate, reliable and functions as it should
• can continue to meet accuracy requirements when exposed to a range of conditions designed to replicate conditions in the field

We base our performance tests on the specifications detailed in the pattern approval requirements.

We conduct:

• temperature testing
• damp heat, steady-state and cyclic humidity testing
• AC and DC power variation testing
• immunity to radiated interference testing
• immunity to conducted radio-frequency field strengths testing
• electrostatic discharge testing
• line-borne interference testing

We will contact you with the results of each test after we perform them.

Acceptance of test results

We accept test results from other ISO 17025 accredited facilities with appropriate scope of accreditation. We generally do not accept manufacturer’s test results.

To help us to determine acceptability, you can provide:

• full detailed test reports, including test results
• details of the laboratory that conducted the test including its ISO 17025 certificate of accreditation, if they are not part of a formal mutual acceptance agreement

We have mutual acceptance agreements with:

• Office for Product Safety and Standards in the United Kingdom to accept test reports for:
  • load cells
  • non-automatic weighing instruments
  • water meters
  • continuous totalising automatic weighing instruments
  • automatic catchweighing instruments
  • automatic gravimetric filling instruments
  • automatic rail-weighbridges
  • discontinuous totalising automatic weighing instruments
  • fuel dispensers (excluding for liquefied petroleum gas)
  • multi-dimensional instruments
• Netherlands Measurement Institute to accept test reports for:
  • load cells
  • non-automatic weighing instruments
  • fuel dispensers (excluding liquefied petroleum gas)
• Trading Standards in New Zealand to accept test reports for non-automatic weighing instruments
• countries participating in the International Organization of Legal Metrology (OIML) mutual acceptance arrangement and the OIML certification system

Approving authorities

We approve these instruments, but we appoint approving authorities to test:

• utility meters
• evidential breath analysers

Find an approving authority to test your measuring instrument for pattern approval.

Decision to issue a certificate of approval

After we have assessed your instrument pattern and documentation, we make a decision. If we approve your instrument, then we issue a certificate of approval.

Non-passing instruments

We will notify you if we assess your instrument pattern and make the decision not to pass it. You will be able to make modifications and resubmit your instrument.

Read more 

• Read the pattern approval requirements for your instrument
• Read the pattern approval guidelines and procedures for your instrument
• Find an approving authority to test utility meters and evidential breath analysers

Contact us    

• Email patternapproval@measurement.gov.au
• Phone 1300 686 664
• Write to us at Pattern Approval Section, National Measurement Institute, 36 Bradfield Road, West Lindfield, NSW 2070