Each NGER measurement criterion rests on a different kind of evidence. Because the Clean Energy Regulator treats the criteria as indicators of data quality, the evidence is what an auditor tests.
Key points
- Criterion A needs facility-specific vendor invoices or delivery records
- AA adds surveys, density and reconciliation
- AAA needs calibration traceable to a measurement requirement
- BBB needs a documented industry-practice estimate
- Records are kept for five years and must be accessible to auditors
Evidence by criterion
| Criterion | Core evidence |
|---|---|
| A | Invoices issued by the vendor. Section 1.8 of the Determination states that an invoice includes a delivery record, and the Regulator’s guideline states that each invoice must refer to a particular amount of a particular fuel delivered to a particular facility. |
| AA | Invoices plus the stockpile estimate: survey results, bulk density measurements, the book quantity and, under the error allowance approach, the tolerance test. |
| AAA | Measurements from equipment calibrated to a measurement requirement, with calibration traceable to the National Measurement Act 1960 or an equivalent standard. For gas, flow computer records (section 2.36) and evidence that transmitters, flow devices and chromatographs meet the accuracy and calibration requirements in sections 2.31 to 2.37. |
| BBB | The industry practice used, why no commercial transaction or calibrated equipment applied, and how the estimate meets the principles in section 1.13. |
What the Regulator recommends keeping
The Regulator’s record-keeping page lists the methods and measurement criteria used and the reasons they were selected, along with records of business decisions on controlling corporation, corporate group and facility. Records can be paper or electronic, must be accessible to auditors, and are kept for five years from the end of the reporting year.
Common weak points
- Invoices that cover several sites or fuels without an allocation to each facility.
- Stockpile surveys without density results or reconciliation to the book quantity.
- Meters without current calibration certificates, which undermines criterion AAA.
- Contractor fuel estimated by industry practice when it was bought commercially, which rules out criterion BBB.
Why it matters
For large facilities, the same fuel quantities feed uncertainty reporting, Safeguard covered emissions and audits under the NGER Act 2007. Evidence that ties each quantity to its criterion is the difference between a figure that stands up and one that has to be resubmitted.
References & sources
Primary regulatory documents and authoritative references underpinning this answer.