Credentials · Certification
National Board R Certificate of Authorization (R Stamp)
An organizational accreditation, not a personal one: the National Board authorizes a repair firm to repair and alter pressure-retaining items and to apply the R symbol stamp. It is held by the shop, never by the welder.
Verified requirements
| Where | Expires | Renewal | Continuing education |
|---|---|---|---|
| United States (federal) | Yes | 3 years | — |
Verified against the issuing authority. Always confirm current rules before acting.