Glossary›Assurance, audit evidence and working papers›Audit trail (emissions data)
Glossary term
Cluster A · A11
Tier 1 · differentiator
Audit trail (emissions data)
Definition
An audit trail is the unbroken documented path from a figure in your climate disclosure back to the original source record, through every calculation and adjustment in between. An assurance provider follows the trail in both directions. Where the trail breaks, the number cannot be supported and the disclosure is at risk.
No governing instrument
· practice requirement derived from the ASSA 5000 evidence obligations ·
Practice
On this page
In practice
“Audit trail” is used as a marketing adjective across this market. The operational meaning is narrow and testable. For a single reported figure the trail has five links: the source record, the extraction of the activity quantity from it, the unit conversion, the emission factor applied with its version, and the aggregation into the reported total. If any of those five links is undocumented, the trail is broken at that point.
The most common break is at the third and fourth links. Someone converts a fuel invoice in dollars into litres using an assumed price, or applies a factor from a superseded edition, and the working file records only the result.
What the assurer does with it
The assurer walks the trail in both directions on a sample. Forwards is vouching: pick a source document, follow it into the report, confirm it arrived correctly. Backwards is tracing: pick a reported figure, follow it back to source. Both are needed, because forwards tests accuracy and backwards tests existence, and neither tests completeness. What they reject is a trail that requires a person to explain it. If the file only makes sense when the analyst who built it is in the room, the trail does not exist for assurance purposes.
Commonly confused with
A system log. Software audit trails record who changed what in the application. That is data lineage, and it is one input to the audit trail, not the whole of it.
Sources
1
ASSA 5000 General Requirements for Sustainability Assurance Engagements
AUASB
2
Review status
Review required
Last reviewed
15 September 2026
Editorial pass, unsigned
Reviewer required
Registered company auditor
Next scheduled review
1 July 2027
Part of
Cluster A, Assurance, audit evidence and working papers
47 terms on what an assurance provider tests, what they accept as evidence, and what a preparer has to be able to produce.
Related terms
The machine-readable half of the trail
Where the trail has to terminate
What keeps the trail intact after the model is rerun
Related questions
What is the audit trail our auditor expects?
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An unbroken path from every reported number back to a document you did not create for the report, such as an invoice, a meter reading, a fuel card statement or a signed minute. At each step the trail shows the data used, the factor applied, the calculation, and who reviewed it.
What evidence do we need for each emissions number?
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Every reported number needs a source document you did not create for the report, the activity data drawn from it, the emission factor and its published edition, and the calculation joining them. Fleet fuel needs litres from fuel card statements, electricity needs kWh by site from retailer invoices with the matching state factor, and refrigerants need kilograms by gas type from service records.
Can we use spreadsheets, or will the auditor reject them?
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Spreadsheets are acceptable and no Australian standard requires software. What gets rejected is an unauditable spreadsheet: hard-coded numbers with no source, broken formula chains, no version control and no record of who changed what. A disciplined spreadsheet passes assurance and an undisciplined system does not.
Other terms in this cluster
Audit trail (emissions data)