Primary Data: The EPD Accuracy Multiplier
Specifiers no longer settle for industry-average footprints. Miss too much primary data and your environmental product declaration picks up a 30 % uncertainty surcharge that can price you straight out of a bid (NMD, 2025). Here’s why getting plant-level numbers matters, and how to gather them without grinding production to a halt.
Primary vs. secondary in 60 seconds
Secondary data are the crowd blends sitting in public LCI libraries. Primary data are the direct meter reads, weigh-tickets, and supplier LCAs tied to your own line. Both are allowed, but only one is sharp enough to convince a skeptical carbon accountant.
Why specifiers care about the source
Embodied carbon already makes up about 7 % of global energy-system emissions (IEA, 2024). When project teams chase every kilogram of CO₂, they trust EPDs built on real factory data, not averages. A product-specific EPD can swing a material choice worth millions because the delta between two bidders often comes down to single-digit kilograms of GWP.
The 30 % penalty of generic proxies
Dutch program operator NMD slaps a 30 % "generic tax" on calculations that rely on category 3 data, explicitly to push manufacturers toward category 1 primary datasets (NMD, 2025). Translate that to a steel deck panel and you might add 120 kg CO₂e per tonne,enough to bump you out of a shortlist.
Collecting plant-level numbers without paralysis
Finance knows kWh off the utility bill. Maintenance logs diesel for the forklifts. QC tracks scrap rates down to the gram. The raw figures already live inside your ERP; they just need tidy extraction and clear allocation. We map each field once, automate the pull, and let engineers stay on the line instead of spelunking spreadsheets.
Supplier data: the hidden jackpot
Upstream materials often dominate impact. One glass producer saw a 23 % GWP drop by swapping generic cullet data for furnace-specific numbers in its EPD (Meta-analysis in Buildings, 2024). Start with the top-three mass inputs and ask those suppliers for their latest EPD or verified LCI—chances are they now have one.
Avoiding the time sink
Chasing primary data can feel like herding cats: different time zones, non-responsive vendors, missing NDA paperwork. A white-glove EPD team tackles that chase for you, keeps the reminder cadence polite but persistent, and validates every figure before it hits the LCA model. Your role shrinks to green-lighting anomalies, not doing the footwork.
Put truth in every tonne
Primary data will not just tidy your EPD; it will keep you in the game as procurement rules tighten around the world. Treat every missing meter read as a cost, not a convenience, and the ROI becomes obvious.
Frequently Asked Questions
How much primary data do I need for an EN 15804 compliant EPD?
The standard does not set a strict percentage, but most program operators expect primary data for all foreground processes and the top 90 % of mass or energy flows. Anything less can trigger higher uncertainty factors (EN 15804+A2, 2019).
About the Author
With a passion for sustainability and a love for complex data, Toby helps manufacturers efficiently collect data from across their organization and get their EPDs done right. He’s especially interested in how AI can support human expertise, helping R&D and factory teams work faster, smarter, and with less friction.
