Performing

Phases of the assurance process — performing

During the performing phase, the audit team completes the procedures developed during the planning phase. These procedures should help the auditor:

● reduce the assurance risk to an acceptable level

● gather enough evidence to give a conclusion about whether the audited body has complied with all relevant legislation.

There are 5 steps to performing analytical procedures:

1. assess the reliability of data

2. develop an independent expectation

3. define a significant difference in threshold

4. compute the differences

5. investigate differences and conclude.

Evidence-gathering techniques include:

● External confirmation: getting confirmation from a third party. For example, checking reported information with a third party.

● Inspection: examining records and documents. For example, reviewing internal metering systems to check they exist and are functioning properly.

● Observation: looking at a process or procedure being performed by the audited body. Generally, this is conducted when the process doesn't leave an audit trail of documents. For example, touring facilities or observing the collection and reporting of data.

● Enquiry: asking personnel of the audited body to explain how they make decisions. For example, discussing how they made decisions while doing calculations.

● Re-calculation: conducting independent calculations to confirm the audited body's calculations to check accuracy. It also involves checking the completeness of source documents and records. For example, re-computing the audited body's greenhouse gas emissions calculations.

Section 3.9 onwards of the Greenhouse Gas Reporting (Audit) Codes of Practice 2025 outlines how to perform an assurance engagement.

Importance of documentation

Assurance documentation is a key part of an assurance engagement.

Documentation helps auditors review and evaluate the evidence and proposed conclusion before the assurance engagement report is finalised.

The documentation must provide:

● a sufficient appropriate record of the basis for the audit team leader's report

● evidence the assurance engagement was performed in accordance with the Determination.

Documentation should also show how the audit team followed other guidance like ISAE 3000.

An experienced auditor with no previous connection to the engagement should be able to use the documentation to understand:

● the nature, timing, and extent of the procedures performed, including details of who performed and reviewed the assurance work and when

● the results of the procedures and evidence obtained

● significant matters arising during the engagement and the conclusions reached.

Documentation must be kept for 5 years after the date the assurance engagement report is signed.