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NIST Workshop: Assessment of Mass Balance Accounting Methods for Polymers

Captions are forthcoming. 

The purpose of this workshop is to convene stakeholders associated with mass balance methodologies, including existing standardization and certification programs focused on circular polymers as well as other, comparable industries. Participants will help to identify and assess existing mass balance methodologies, standards, and certification systems that are or may be applicable to the supply chain sustainability of polymers. Further, we aim to assess challenges, including any legal or regulatory barriers, to developing a standard and certification system for circular polymers.  


Workshop objectives: 

  • Identify available mass balance methodologies that are or could be readily standardized to certify circular polymers  

  • Evaluate existing mass balance standards and certification systems that are or may be applicable to supply chain sustainability of polymers 

  • Assess any legal or regulatory barriers to developing a standard and certification system for circular polymers 

Workshop Agenda: 

  • Compare existing certification programs as they relate to circular polymers. 

  • Assess the potential for and limitations of existing certification programs. 

  • Assess legal and regulatory barriers to developing a standard and certification system (e.g., attribution, credit transfers, etc.). 

  • Discern the role NIST can play in advancing mass balance standardization and certification.  

Ideal participants will have a strong background in plastics circularity and mass balance accounting certification tools, especially as they relate to polymers and advanced recycling. This workshop is not intended as an educational program, rather a focused discussion of critical issues in the area. A recording of the event will be available after the workshop for those unable to attend.

Tentative Agenda

Time (ET) Monday, May 3, 2021 Tuesday, May 4, 2021 Wednesday, May 5, 2021
10:00 - 10:30 AM Plenary Talk: Mass balance in the chemical industry: Practical experiences and current political activities in EU Plenary Talk Plenary Talk
10:45 AM - 12:00 PM Session 1: Definitions Session 3: Multi-Site Claims/Credit Transfers Session 5: Legal and Regulatory Barriers/Support
12:00 - 12:30 PM Break Break Break 
12:30 - 1:45 PM Session 2: Allocation  Session 4: Certification Requirements and Interoperability  Session 6: Consumer Awareness and Other Issues
1:45 - 2:00 PM Closing Remarks Closing Remarks Closing Remarks


  • William Hoffman, UL
  • Elena Schmidt, RSB
  • Laura Thompson, GreenBlue
  • Jan Henke, ISCC
  • FSC
  • Matt Rudolf, SCS Global Services
  • Andreas Kicherer, BASF
  • Jason Pierce, Eastman
  • Steve Alexander, Association of Plastics Recylcers 
  • Craig Cookson, American Chemistry Council
  • Kim Cochran, US EPA
  • Jun Wang, Colgate-Palmolive
  • additional speakers to be announced. 


Created March 19, 2021, Updated May 12, 2021