We are working on a big box store in Europe striving to achieve this credit, but differences between the standard Green Label Plus and ACP approaches seems to be causing questions related specifically to caprolactum. We have found a supplier of a carpet with GUT certification, which in almost every category seems to be more stringent than CRI requirements; however, we have been unable to determine whether/how much caprolactam may or may not be in the carpet. As this substance is specifically mentioned in the text of the ACP, we are concerned GBCI may reject our selection and prevent us from earning the IEQc4.3 credit. Does anyone have any experience or additional useful knowledge related to this potential issue?