We are modelling a Chemical mixture used in construction. There are 3 materials in very small quantities 0.3%,0.28% and 0.06%. For two of these there are no Ecoinvent datapoints or close analogues. Our previous OneClick Mentor said we should try and model everything - however my feeling is that these constituents will have minimal impact. Can we ignore these ? And how should we reference that we have done it? During the LCA Bootcamp a 1% cut-off was mentioned I remember. Thanks
Hi David,
It’s generally best to include as much detail as possible in your model. The 1% cut-off rule applies to the total mass and energy contributions. If a component represents less than 1% of the total mass or energy, you can usually exclude it. However, this rule doesn’t apply if that component, even at a low percentage, significantly impacts emissions. For example, if a chemical representing only 0.3% of the total mass contributes 5% of the product’s emissions, you must include it in your model.
Steven