Proposed Implementation Plan for New NFRC 101 Conductivity Values
Revised Link
To all NFRC Product Certification Program (PCP) and Component Modeling Approach (CMA) participants and stakeholders:
NFRC 101,
Procedure for Determining Thermophysical Properties of Materials For Use in NFRC-Approved Software
is the document that lists thermal conductivity values used in NFRC-approved simulations. Generic materials are listed in Appendices A and B while proprietary materials are listed in Appendix C.
The NFRC 101 Task Group will be completing work on an update to the conductivities listed in Appendices A and B in the next few months. This update ensures the values listed in the appendices are accurate and verified through trusted, published sources.
During the update, the TG found new or updated sources for many of the materials listed. In many cases, these new or updated sources changed the value of the thermal conductivity of the material from what was originally published. Additionally, materials that could not be verified through reputable sources were removed and some new materials that could be verified were added. All of the changes were balloted through NFRC’s consensus process, and all were approved with the exception of the conductivity for PVB in Appendix A. A proposed revision to the conductivity for PVB will be balloted soon. No changes were made to Appendix C that lists proprietary materials.
All simulations for NFRC PCP and CMA certification must use the materials listed in NFRC 101. Changes to the thermal conductivity of those materials may change the ratings of whole products which use those materials. In order to maintain accuracy and fairness in the PCP and CMA ratings, the TG is proposing the following implementation plan for the updated Appendices A and B conductivities:
Upon publication, the new conductivities may be used at the manufacturer’s discretion. All conductivity information used in the simulation must come from the same set of data, either the new or the current, not a combination of the two. The manufacturer shall inform the simulation lab which data is to be used.
On January 1, 2021, use of the new conductivities listed in Appendices A and B shall become mandatory.
Between the publication date of the new NFRC 101 data and January 1, 2021:
- The data in the new version of NFRC 101 MAY be used for all new certifications, recertifications, and revisions and addenda to existing products in the product line that are affected by the new data. For revisions and addenda, existing products in the product line that are not affected by the new data shall not be required to be revised, but may be revised at the manufacturer’s discretion. All existing products and product lines in the Certified Products Directory (CPD) at the time of publication of the new NFRC 101 data shall be allowed to remain until the end of the certification cycle for that product line.
- Re-issued reports that consist of company and product name changes only shall not be required to be re-simulated using the new data. Re-issued reports that include additional or different products from the original report shall follow the same rules as given above.
- During the period between publication of the new NFRC 101 data and January 1, 2021 ONLY, the simulation lab shall include the version of NFRC 101 used for the conductivities. This is mandated by Sections 1.1.1.J and 1.1.2.H of NFRC 701.03. It is only being mandated during the time when there are two possible versions of NFRC 101 that are approved for use.
Beginning January 1, 2021:
- The data in the new version of NFRC 101 SHALL be used for all new certifications, recertifications, and revisions and addenda to existing products in the product line that are affected by the new data. For revisions and addenda, existing products in the product line that are not affected by the new data shall not be required to be revised, but may be revised at the manufacturer’s discretion. All existing products and product lines in the Certified Products Directory (CPD) at the time of publication shall be allowed to remain until the end of the certification cycle for that product line.
- Re-issued reports that consist of company and product name changes only shall not be required to be re-simulated using the new data. Re-issued reports that include additional or different products from the original report shall be re-simulated in their entirety using the new NFRC 101 data.
Attached to this bulletin is a comparison of Appendices A and B that shows the existing conductivity for each material and the new conductivity of the material. Where materials were removed or added, that information is also shown.
Please review the attached and be advised that the new NFRC 101 data will likely go into effect on a voluntary basis upon publication of the document and mandatorily on January 1, 2021. The finalized implementation plan is expected to be approved by the end of July 2020. Can be found at the link below.
