A group with four operations can produce a consolidated Scope 1 figure in an afternoon. Each site sends a number, the numbers are added, the total goes in the report. The difficulty starts when someone asks how the site in the second row arrived at its number, and whether it was measured the same way as the site in the third.
Metals and mining is the industry where that question is hardest to answer, and it is also the industry whose disclosure requirements are currently being rewritten.
Key points
- Metals & Mining is one of nine industries the ISSB prioritised for a comprehensive review of the SASB Standards and the IFRS S2 industry guidance.
- That review is still an exposure draft. Comments closed on 30 November 2025 and the ISSB is considering the feedback. Nothing in it is in force.
- The industry metric asks for gross Scope 1 emissions and the percentage covered under emissions-limiting regulations, which is a regulatory exposure question as much as an emissions one.
- Fugitive and process emissions do not come from a fuel invoice, which is why site figures in this industry rest on estimates that have to be documented rather than filed.
The volume that applies, and the review it is inside
IFRS S2 paragraph 32 requires an entity to refer to and consider the applicability of the industry-based metrics. It does not require an entity to apply them in order to state compliance. A miner therefore has to look at Volume 10, Metals & Mining and reach a conclusion about it.
In July 2025 the ISSB proposed a comprehensive review of nine prioritised industries. That is all eight industries in the Extractives & Minerals Processing sector, plus Processed Foods. Metals & Mining is one of the eight.
The status matters more than the content right now. The comment period closed on 30 November 2025, a second exposure draft followed in March 2026, and the project remains at exposure draft stage while the ISSB works through the feedback.
So the practical position for a first cycle is this. Apply the guidance as issued. Expect it to change. Keep your working in a form that survives a change to the metric definitions, because rebuilding a number is far more expensive than re-tagging one.
What the metric actually asks
The Scope 1 metric in this industry is not only an emissions number. It asks for gross global Scope 1 emissions and the percentage of those emissions covered under emissions-limiting regulations.
That second half is easy to skim past. It is a question about where your emissions sit relative to carbon pricing and compliance schemes, and it cannot be answered from the emissions ledger alone. It needs someone to map each source to the regulatory regime of the jurisdiction it sits in, and to be able to show that mapping later.
For a group operating in three or four countries, that mapping is a real piece of work and it is nobody's obvious job.
Intensity, and the argument about the denominator
Alongside absolute emissions, this industry reports on an intensity basis: energy or emissions per tonne. Intensity is how a miner shows improvement while production grows, so it is the number management tends to care about most.
The emissions half of that ratio is the part everyone scrutinises. The denominator is the part that moves the answer.
Tonnes of what, exactly. Ore moved, ore milled, saleable product, or contained metal. Those are four different numbers from the same mine, and they can differ by an order of magnitude. A ratio calculated on contained metal at one site and saleable product at another cannot be added, averaged or compared, and nothing in the arithmetic warns you.
The denominator also comes from somewhere else. Production tonnages belong to the operations and reporting side of the business, on their own timetable and their own definitions, often with a cut-off that does not match the emissions period. An intensity figure therefore joins two datasets that nobody previously had to reconcile.
Decide the basis once, write it down, and disclose it next to the ratio. An intensity number without a stated denominator is not comparable to anything, including your own prior year.
The emissions that do not come from an invoice
Most emissions accounting in ordinary industries is a reconciliation exercise. You have fuel invoices, electricity bills and a factor library. The number is checkable because the inputs are documents.
Mining breaks that pattern in two places.
Fugitive emissions escape from the deposit itself. Methane released from a coal seam or a working face is not purchased, not metered and not invoiced. It is estimated from gas content, production volume and a factor.
Process emissions come from the chemistry rather than the fuel. Smelting and calcination release carbon dioxide from the material being processed, not from combustion. A mass balance across the furnace gives the number.
Both are legitimate. Both are estimates. Neither has an invoice behind it, which means the evidence for them is a calculation and a set of assumptions rather than a document from a third party. That is a different kind of record, and it is the kind most reporting teams are least practised at keeping.
Four sites, four bases, one number
Now put those estimates inside a group. A typical structure has an open pit measuring from fuel, an underground operation measuring from purchased power, a processing plant measuring from a mass balance, and a joint venture where the operator is somebody else.
Each of those is defensible on its own. The group figure adds them together. The problem is that nothing in the addition records that four different measurement bases went into it.
The joint venture is the sharpest version. Your share of its emissions depends on the consolidation approach you chose, and the underlying number was produced by a partner using their factors and their timing. You are disclosing a figure you did not measure, and the only evidence you hold is a report you received. If your partner restates, you restate, and the consolidation question becomes a restatement question.
What a miner has to be able to show
An assurance provider will not test the group total. They will pick two sites and ask the same questions at each.
Which sources are in the boundary for this site, and who decided. For a fugitive or process figure, what method was used, what factor, and what evidence supports the input volumes. Who reviewed the estimate before it left the site. And for the regulatory coverage percentage, which sources were mapped to which scheme, and on what basis.
Sites can usually answer the first two. The third is where the record thins out. A site environmental adviser produces an estimate, emails a spreadsheet to group, and the review that happened between those two events leaves no trace. Eighteen months later the number can be recalculated but the approval cannot be evidenced, which is a sign-off problem rather than a measurement problem, and the same gap the reproducibility test exposes.
The fourth is worse, because the regulatory mapping is often held in one person's knowledge and never written down at all.
If you take one thing into a first cycle in this industry, make it this: the estimates are fine, but an estimate without a documented method, a named reviewer and a date is not evidence. It is an assertion, and assertions do not survive a sample.
Common questions
Is Metals & Mining affected by the ISSB review of the SASB Standards?
Yes. It is one of the nine prioritised industries, being all eight in the Extractives & Minerals Processing sector plus Processed Foods. The proposals are at exposure draft stage. The comment period closed on 30 November 2025 and the ISSB is considering the feedback, so nothing proposed is currently in force.
Do I have to apply the industry-based metrics for mining?
No. Paragraph 32 requires an entity to refer to and consider their applicability. Applying them is not a condition of stating compliance with IFRS S2. What you cannot do is skip the consideration, or fail to support the conclusion you reached.
How should fugitive emissions be evidenced?
By the method rather than by a document. Record the estimation approach, the factor and its source, the input volumes and where they came from, and the person who reviewed the result. There is no invoice to file, so the calculation and its approval are the evidence.
What about a joint venture we do not operate?
Your consolidation approach determines the share you report, and the underlying figure comes from the operator. Keep the report you received, the date, the version, and the basis the operator used. Treat a partner restatement as a restatement risk of your own.
Where do you stand against IFRS S2?
The readiness diagnostic scores governance, evidence and controls across the four pillars. For the structure of the standard itself, see the IFRS S2 reference.