Fabric Ducts vs Galvanized

Has anyone looked at embodied carbon of fabric vs galvanized duct. Im super new to EPD’s and a little confused. My understanding is that the EPD’s report per unit weight of product so its a bit tricky to compare 1kg of fabric vs 1kg of steel - I imagine fabric is many times lighter. Any guidance would be super helpful!

Hi EPDs can be also done by lenght (1 meter or imperial) and then the weight is declared. Different products use different declared units.