How to Find the Carbon Footprint of a Product in an EPD

Environmental Product Declarations (EPDs) are powerful tools, but they’re not always user-friendly. If you’re not used to reading one, it can feel like digging through technical noise just to find a single number.

That number? The carbon footprint of the product.

Step 1: Find the Right Section

Scroll through the EPD until you reach the section titled: “Results of the environmental performance indicators”

This is where all the key emissions data is reported. Usually, the first table here is titled: “Mandatory impact category indicators” (or something similar)

Step 2: Look for the Global Warming Potential (GWP)

In this table, you’re looking for the row labeled: Climate change – total or GWP – total (Global Warming Potential – total)

Make sure you’re looking at the total value — not just GWP-fossil or GWP-biogenic. EPDs break it into categories, but for understanding the total CO₂-equivalent emissions, you need the full sum.

Step 3: Different Modules

The tables show modules A-D.

• A1-A3: Product stage
• A4-A5: Construction stage
• B: Use stage
• C: End of life cycle
• D: Other (reuse and recycling potential ...)

If you’re looking for the carbon footprint of product manufacturing (also called cradle-to-gate), you should be looking for A1–A3. This includes raw material supply (A1), transport (A2) and manufacturing (A3).

If the EPD gives you a total GWP for A1–A3 already, great. If not, simply add the three values together.

A1 + A2 + A3 = total product carbon footprint.

Step 4: Understand the Numbers (What’s With the E?)

You might see a value like: 9.16E+02 (kg CO₂ e)

This is a scientific notation. 'E' stands for exponent and represents 'ten raised to the power of'.

• 'E+02' means 10 raised to the power of 2 (which is 100)
• So, 9.16E+02 means 9.16 × 100 = 916

 That’s 916 kg CO₂-equivalent emissions. 

 Here are a few quick conversions for reference:

• E+00 = 10⁰ = 1
• E+01 = 10¹ = 10
• E+02 = 10² = 100
• E+03 = 10³ = 1000

If A1, A2, and A3 are in different exponents, convert them to the same unit before adding. For example:

• A1: 4.10E+02 = 410
• A2: 3.10E+01 = 31
• A3: 4.75E+02 = 475

 Total: 916 kg CO₂ e