your portal to more fun in scale model railroading
your portal to more fun in scale model railroading
The NMRA, in its standards and recommended practices, addresses only the specific standards and recommended practices for model railroads. These standards and recommended practices do not address any legal requirements. It is the responsibility of the manufacturer to determine if their product conforms to all applicable governmental laws and regulations.
| Document | Posted | Comment Period Ends |
| S-3.2 Track Standard Scale | 26-Apr-2026 | 21-May-2026 |
| S-4.2 Wheels Standard Scale | 4-Apr-2026 | 21-May-2026 |
| S-9.1 Electrical Standards for DCC | 1-May-2026 | 11-Jun-2026 |
| S-9.1.3 Decoder Power Modes | 5-May-2026 | Not Set |
| S-9.2.1 DCC Extended Packet Formats | 15-Nov-2025 | Not Set |
| S-9.2.1.1 Advanced Extended Packet Formats | 23-Jun-2024 | Not Set |
| S-9.2.2 Configuration Variables | 8-May-2026 | Not Set |
| S-9.3.2 BiDirectional Communication | 10-Apr-2026 | 11-Jun-2026 |
| S-9.4.1 SUSI Bus Communication Interface | 29-Jan-2026 | Not Set |
| S-9.4.2 SUSI Bus Configuration Variables | 29-Jan-2026 | Not Set |
| S-9.4.3 SUSI Bus Bidirectional Extension | 29-Jan-2026 | Not Set |
| S-9.4.4 SUSI Train Bus Extension Shift Register | 29-Jan-2026 | Not Set |
| RP-11 Curvature an d Rolling Stock | 15-Feb-2026 | Not Set |
| TN-11 Curvature and Rolling Stock | 15-Feb-2026 | Not Set |
| RP-37 Locomotive and Tender Drawbars | 21-Mar-2026 | Not Set |
| Document | Posted | Voting Ends |
|---|---|---|
| S-9.1.1.6 E24 Decoder Interface | 1-May-2026 | 11-Jun-2026 midnight CDT |
| TN-9.1.1.6 E24 Decoder Interface | 1-May-2026 | 11-Jun-2026 midnight CDT |
| Document | Associated | Posted | Comments End |
|---|---|---|---|
| There are no documents for review | None |
| Document | Submitted | Approved |
|---|---|---|
| There are no documents for BOD approval | at this time |
Previous document revisions were submitted to the Board of Directors and approved are now on the Standards page.
If you need additional information or wish to make further inquires regarding NMRA Standards, please contact the NMRA Standards & Conformance Department at tech-chair [at] nmra.org, CIManager [at] nmra.org or dcc-manager [at] nmra.org
National Model Railroad Association, Inc.
Department #635
P.O. Box 1328, Soddy Daisy TN 37384-1328
Phone: (423) 892-2846 - Fax: (423) 899-4869
Revised by Brian Barnt 5-Nov-26