Top 10 Things Checked in Emissions Verification (and What Companies Keep Missing)

Top 10 Things Checked in Emissions Verification (and What Companies Keep Missing)

Emissions inventory verification is perceived by most teams as "is the calculation correct?" Verification teams look at the calculation. But what they're really looking for is the reliability of the system. Where did the data come from, who produced it, how did it change, what assumptions were used for calculation, what boundaries were used for reporting.

In this article, we cover the 10 most questioned topics in the verification process. For each, we share common mistakes and preparation recommendations.

1. Organizational boundary

The first thing the verification team looks at is what the inventory covers. Which facilities, companies, or operations are included in scope? Which ones are left out?

The consolidation approach is critical. GHG Protocol offers three approaches: financial control, operational control, and equity share. Which approach is selected and its justification must be documented. The approach should not be changed in different reporting periods, or changes should be clearly stated.

Common mistake: Excluding group companies, joint ventures, or outsourced operations without justification. The verifier questions the logic of these decisions.

2. Base year selection and consistency

The base year is the reference point for emission reduction targets and performance tracking. The verifier asks: By what criteria was the base year selected? Is data quality sufficient? How were structural changes handled?

There should be a recalculation policy. When company structure changes (acquisition, sale, capacity change), whether the base year will be recalculated and which thresholds will trigger it should be determined in advance.

Common mistake: Base year is not updated after acquisitions or sales. This breaks comparability.

3. Data collection process

Data quality starts with process quality. The verifier wants to understand: From which systems, at what frequency, by whom was data collected? Manual entry or automatic extraction?

Standard data collection templates should be used. The template should include data fields, units, source references, and validation rules.

Common mistake: Data is collected scattered in email attachments. Source traceability is lost. Unit conversions are not documented.

4. Audit trail

The path from raw data to final report must be traceable. Each step must be documented. Changes must be recorded.

The audit trail should show: Raw data source (invoice, meter reading, ERP record) → intermediate calculation → emission factor application → final result.

Common mistake: Only the result appears in the calculation file. Raw data connection is broken. The verifier cannot trace back to the source.

5. Emission factor selection

Which emission factor sources were used and the selection rationale are critical questions. The verifier checks: Are the factors current? Are they geographically appropriate? Are they scope-appropriate (well-to-tank vs tank-to-wheel)?

Factor selection criteria: First primary data (supplier data), then regional factors (national databases), finally global factors (IPCC default values).

Common mistake: Factor source is not specified. Factors from different years are mixed. Well-to-tank and tank-to-wheel difference is ignored.

6. Calculation methodology

The verifier wants to understand the logic of the calculation. What formulas were used? Are unit conversions correct? Are assumptions clear?

The calculation file should be transparent. Formulas should be visible, hardcoded values should be justified, assumptions should be documented.

Common mistake: Calculation is presented only as a result. Formula and intermediate steps remain hidden. Verifier cannot perform checks.

7. Exclusions

Every inventory can exclude certain sources. But justification must be provided. The verifier asks: Which sources are excluded? Is a materiality threshold defined?

GHG Protocol does not define a materiality threshold but expects transparency. Excluded sources should be expressed as a percentage of total emissions.

Common mistake: Small facilities or emission sources are excluded without justification. Total impact is unknown.

Materiality threshold examples: Some companies use a 1% or 5% threshold. For example, sources that make up less than 1% of total emissions can be excluded. But this decision should be documented transparently and the total of excluded sources should be reported.

8. Uncertainty and data quality

Data quality assessment shows the reliability of the inventory. The verifier asks: Is primary and secondary data distinction made? Are uncertainty sources identified? Is there an improvement plan?

Data quality indicators: Geographic appropriateness, temporal appropriateness, technological appropriateness, completeness.

Common mistake: All data is considered equal quality. Uncertainty assessment is not performed.

9. Internal control and approval

How does the data approval process work? Who checks, who approves? Are responsibilities clear?

Four-eyes principle: The person preparing the data and the person approving should be different people. Control points and signature/approval records should be kept.

Common mistake: One person collects data, calculates, and approves. There is no internal control.

10. Reporting consistency

Do the figures in the report match the calculation files? Is rounding consistent? Can comparison with previous periods be made?

Consistency checks: Does total = sum of sub-items? Was the same methodology used as last year? Are changes explained?

Common mistake: Report and calculation file are different versions. Figures don't match.

Evidence requirements per control point

Key evidence to prepare for each control point:

• Organizational boundary: Company structure diagram, consolidation approach justification, group companies list
• Base year: Base year selection justification, recalculation policy, structural change records
• Data collection: Templates, data flow diagram, responsibility matrix
• Audit trail: Raw data documents (invoices, meter readings), intermediate calculation files, formula explanations
• Emission factors: Factor source and version, selection justification, geographic and temporal appropriateness note
• Calculation: Formula documentation, assumptions list, unit conversion checks
• Internal control: Approval flow, four-eyes principle evidence, control point signature/approval records

Verification preparation recommendations

1. Conduct internal review before verification
2. Keep all source documents accessible
3. Prepare calculation file to be transparent and traceable
4. Document methodology and assumptions
5. Justify organizational boundary and exclusions

Conclusion

Verification tests the entire system, not a single calculation. The verifier looks for the reliability of the process behind the number. Being prepared for these 10 control points speeds up the verification process, reduces finding risk, and increases stakeholder confidence.