National Board accredited programs are evidence that acceptable codes and standards are followed, jurisdictional and regulatory requirements are understood, and in-service repair and testing methods are applied satisfactorily.
The National Board maintains four separate accreditation programs, issuing certificates of authorization and corresponding stamps and marks for the repair and alteration of boilers and pressure vessels (R), the repair/replacement of nuclear components (NR), the repair of pressure relief valves (VR), and the “test only” (T/O) in-service testing of pressure relief valves. National Board accredited programs — and their associated stamps and marks — are recognized worldwide. They are evidence that acceptable codes and standards are followed, jurisdictional and regulatory requirements are understood, and in-service repair and testing methods are applied satisfactorily. NBBI accreditation ensures users that boilers, pressure vessels, and pressure-retaining items have been repaired or replaced properly and will operate safely.