This page belongs to: National Measurement Institute

Issuing certificates of approval

If your instrument complies with the pattern approval process, we issue a certificate of approval.

We will consult with you throughout the pattern approval process. This includes consulting to finalise the technical information presented in the certificate.

Types of certificates and approvals

We list some of the more common certificates and approval conditions on this webpage. Read about all certificate types in the approval and certification procedures.

Interim certificate

We may issue an interim certificate while we finalise the certificate.

Final certificate  

You may need to provide us with extra technical information or drawings to describe the instrument. 

We’ll draft and send you the final certificate for your consideration.

When you have agreed to the draft, we’ll issue a final certificate.

General supplementary certificate

If your certificate of approval allows you to connect an auxiliary or peripheral device—such as a printer or fuel dispenser nozzle—it may refer to a general supplementary certificate of approval.

If you supply auxiliary devices to third parties along with your instrument, you must ensure that it complies with the relevant general certificates.

Unless we ask, you do not need to submit auxiliary devices for pattern approval.

If you have any questions, contact our pattern approval section

Internationally recognised certificates

We can issue International Organisation of Legal Metrology (OIML) certificates of conformity along with a test reports for instruments within the scope of our accreditation.

You can use these to get your instrument approved for trade use in other countries. These documents provide evidence that we have evaluated your instrument and it complies with the requirements of an OIML recommendation for patterns of instruments in use for trade.

We issue OIML certificates for:

  • continuous totalising automatic weighing instruments
  • non-automatic weighing instruments.

Special clauses

Some certificates of approval may include special clauses. Under these clauses, you may need to provide extra information like copies of test results or instrument locations. 

Instruments approved for legal use

Some measuring instruments have been approved for legal use only. These instruments can’t be used for trade as they may have been assessed against different criteria and have different controls around their use.

After you get a certificate

Manufacturing, importing and supplying measuring instruments

When you import or build instruments under this certificate, you must:

  • construct the instrument in accordance with the certificate of approval and the technical schedule
  • mark each instrument with its pattern approval number and information stated on the certificate of approval.

You may also get the instrument:

To find a servicing licensee to verify your measuring instrument, email

Notify us of changes

You must notify us if you make any changes to the design/software of the instrument after we issue the certificate of approval. We may need to add a variant or make other amendments to the certificate.

You must also notify us if your company or contact details change.

See approval and certification procedures for more information on variations.

Major variations

Use the pattern approval application form to request major variations to your certificate.

Apply for a major certificate variation

Apply for new certificates, variations, provisional certificates, cancellations and reviews. Also request instrument test reports (non-pattern approval testing) or consultation services.

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