Data-center suppliers are no longer being asked only for a sustainability statement. Buyers increasingly want a product-level embodied-carbon result, the method behind it, and enough context to use the figure in procurement and project accounting.

That shift matters to manufacturers of cooling equipment, electrical systems, piping, cable management, generators and the materials used to build data centers. The request may arrive as an EPD requirement, a supplier questionnaire or a carbon-disclosure template. The format can vary, but the direction is consistent: buyers want environmental data that can move through their own systems and stand up to review.

Environmental Product Declarations (EPDs) are the gold standard for standardized, independently verified product environmental disclosure. They combine life-cycle results, category-specific rules and third-party review in a public declaration. Where a buyer or project specification requires an EPD, a self-declared carbon figure is not a substitute. This article explains what buyers need to see and how suppliers can prepare.

Why Data-Center Buyers Need Product-Level Carbon Data

A data-center operator can estimate operational emissions from the energy used to run a facility. Embodied emissions are different. They arise from producing and transporting the equipment and materials that make up the facility, so the operator depends on suppliers for much of the underlying information.

In its 2024 supplier call, the iMasons Climate Accord, an industry initiative run by Infrastructure Masons to reduce the climate impact of digital infrastructure, called on vendors to create verified EPDs, follow common Product Category Rules where applicable and make the declarations available through shared databases. The stated purpose was practical. Owners and operators need supplier data to estimate embodied emissions, establish baselines and include carbon in procurement decisions.

The 2025 Open Compute Project and iMasons Embodied Carbon Disclosure Base Specification pushes the same problem toward a common data structure. It asks vendors to provide an embodied-carbon result together with context such as the calculation methodology, system boundary, data sources and assumptions.

A carbon figure is useful only when the buyer can tell what product it covers, how it was calculated and what sits inside the boundary.

That is why a single number copied into a spreadsheet is rarely the end state. The buyer needs enough information to aggregate the result into a project total and to understand whether two disclosures are meaningfully comparable.

Why European Developments Make Product Evidence More Valuable

In an April 2026 article, the European Committee for Standardization explains how the updated EN 15978 building-assessment standard brings together EPD data and other information to assess environmental performance across a building’s life cycle. Product disclosures become inputs to a wider building assessment, rather than standalone sustainability documents.

The European Commission’s current guidance also sets out the move toward calculating and disclosing whole-life carbon for new buildings: those larger than 1,000 square metres from 2028, extending to all new buildings from 2030, under the Energy Performance of Buildings Directive.

These are broader building requirements, with application governed by the relevant national rules and project scope. They are not a blanket requirement for every data-center equipment supplier to publish an EPD today. For suppliers serving European projects, the practical implication is to prepare product evidence that can feed the customer’s building assessment. EPDs provide a standardized, independently verified foundation for that work.

What Suppliers Are Being Asked to Disclose

The Open Compute Project base specification is intentionally flexible about calculation methods. A supplier may be early in its carbon-measurement program and use one of several recognized approaches. The important step is to pair the result with the method and context needed to interpret it.

A useful supplier disclosure commonly identifies:

• The product: model, dimensions, material, configuration and other characteristics needed to know what the result represents.

• The result and unit: the embodied-carbon figure and the unit or reference quantity used.

• The system boundary: which life-cycle stages are included, such as raw materials, transport to manufacturing and manufacturing.

• The method: whether the result comes from an LCA, product carbon footprint, EPD or another accepted estimation method.

• The evidence: primary manufacturing data, supplier data, secondary datasets, emission factors and the period represented.

• The assurance level: whether the result is self-declared or independently verified.

This context is valuable even before a supplier has a full EPD. It gives the buyer a more usable answer and exposes the gaps the supplier will need to close.

What a Useful Response Looks Like

Consider an illustrative cooling-equipment supplier whose customer asks for the carbon footprint of a unit. A result without a model number or boundary leaves the customer guessing: does it cover the supplied configuration, and does it include manufacturing alone or also lifetime electricity use?

A useful response identifies the configuration, reference quantity, included stages, calculation method, data period and verification status alongside the result. If the customer needs a different scope, the supplier can identify the gap before investing in work that will not answer the request.

Why EPDs Are the Gold Standard for Product Disclosure

An Environmental Product Declaration is a standardized public disclosure based on a Life Cycle Assessment and an applicable Product Category Rule. Under an ISO 14025 program, an independent verifier reviews the underlying work before a program operator publishes the declaration.

That makes an EPD different from a general carbon response in three important ways:

1. The calculation follows category-specific rules. The PCR defines how the study is conducted and what the declaration reports.

2. The work is independently reviewed. The verifier checks the methodology, evidence, calculations and documentation.

3. The result is published in a recognized format. Buyers can find and use the declaration without reconstructing the supplier’s method from a questionnaire.

EPDs give buyers a standardized, independently verified basis for reviewing product environmental information. They report the indicators required by the applicable PCR, extending beyond a carbon-only result. Comparison still requires compatible product functions, units, boundaries and methods.

Buyer and project requirements determine the required deliverable. If the specification asks for an EPD, plan for the verified declaration from the start. A questionnaire response or product carbon footprint may answer an earlier request, but it does not replace an explicitly required EPD. The Open Compute Project specification supports several disclosure approaches; alignment with its format alone does not establish third-party verification.

Why Method Transparency Matters as Much as the Result

Two products can carry numbers that look comparable while using different boundaries, reference units or source data. A buyer cannot responsibly treat those figures as interchangeable without checking the surrounding method.

For suppliers, this creates a straightforward preparation task. Keep the number connected to the product definition, model inputs, source documents, assumptions and calculation version that produced it. If the product changes, the evidence trail should make clear whether the result still applies.

This is also where one-off disclosure work becomes difficult to maintain. A new size, material, facility or supplier can change the inputs. When the original calculation lives in disconnected spreadsheets and email attachments, answering the next customer request often means reconstructing the work.

A structured model and evidence record make the disclosure repeatable. The same governed inputs can support a buyer questionnaire today and a verification-ready EPD program as the requirement matures.

How Suppliers Can Prepare Before the Next Request

Manufacturers do not need to wait for a procurement deadline to organize the work.

Start with five questions:

1. Which products are appearing in data-center bids or customer questionnaires?

2. What carbon or EPD language is already showing up in specifications and supplier requests?

3. Which product definitions, bills of materials, facilities and suppliers sit behind those products?

4. What calculation methods and source evidence already exist?

5. Which gaps would prevent an independent reviewer from following the result back to its inputs?

The answers reveal whether the immediate need is a structured supplier disclosure, a product carbon footprint or an EPD. They also show whether the company is preparing one answer for one product or building a repeatable capability across a catalog.

Build One Model, Generate Many Outputs

The progression is clear: the industry’s 2024 call for verified EPDs, the 2025 common disclosure framework and Europe’s 2026 building-assessment developments all increase the value of traceable product evidence. Buyers need information they can use, review and connect to their own decisions.

CarbonGraph’s approach is to build a reusable life cycle assessment model, connect it to product and manufacturing evidence, and use that foundation to generate multiple outputs. A structured model can support product-configuration results, customer disclosure responses and the technical documentation needed for EPD verification. Each output stays connected to the inputs, assumptions and calculation version behind it.

Building one model does not mean one EPD automatically covers every product. Declaration coverage, reporting format and verification still follow the applicable product category and program rules. The reusable model is the foundation that keeps those different outputs consistent and makes the next customer request easier to answer.

Build the evidence once, maintain the model as products change, and generate the outputs each buyer needs from that shared foundation.

For more on scaling this work, read Data Center Suppliers Need EPDs for the Whole Product Line.

Have a customer carbon questionnaire or EPD request? Book a CarbonGraph walkthrough to discuss your product scope, existing evidence and the gaps to a verification-ready workflow. Start with the buyer’s acceptance criteria, then build one reusable model that can support the next request too.