An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Reference functional model for the activities and processes involved in production (e.g., designing, manufacturing, and recovering products/materials) in a circular economy. The model includes inputs