National Board of Boiler and Pressure Vessel Inspectors (NBBI)
NBBI is dedicated to standardizing best practices regarding the construction, installation, inspection, and repair of boilers, pressure vessels, and related equipment. The organization also certifies inspectors, accredits repair organizations, and maintains registration systems that help industries maintain a reliable approach to pressure equipment safety.
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Popular NBBI Standards
| Standard Code | Title | Format Available |
|---|---|---|
| NBBI NB23-2025 | National Board Inspection Code (NBIC), 2025 Edition, Complete Set (Four Volumes) | PDF, Print |
| NBBI NB23 Part 1 | National Board Inspection Code (NBIC), Part 1 – Installation | PDF, Print |
| NBBI NB23 Part 2 | National Board Inspection Code (NBIC), Part 2 – Inspection | PDF, Print |
| NBBI NB23 Part 3 | National Board Inspection Code (NBIC), Part 3 – Repairs and Alterations | PDF, Print |
| NBBI NB23 Part 4 | National Board Inspection Code (NBIC), Part 4 – Pressure Relief Devices | PDF, Print |
What Are NBBI Standards?
The National Board of Boiler and Pressure Vessel Inspectors (NBBI) was established in 1919 in response to a rising number of industrial accidents caused by unsafe boilers and pressure vessels. At the time, rapid industrialization had outpaced the development of consistent safety requirements, leading to significant risks for workers and the public. Various jurisdictions recognized the need for coordinated regulation and standardized inspection practices, ultimately forming the National Board to unify their efforts and promote safer engineering practices across North America.
Initially, the National Board focused on creating uniform inspection qualifications and expectations to ensure the integrity of boilers and pressure vessels. Before this, each jurisdiction operated independently, resulting in inconsistent competencies and uneven enforcement of safety rules. By developing a centralized certification program and working closely with the emerging ASME Boiler and Pressure Vessel Code, the National Board helped set a national benchmark for inspector expertise and technical knowledge.
Over time, the organization expanded its role by establishing the National Board Inspection Code (NBIC), a comprehensive set of rules covering the installation, inspection, repair, and alteration of pressure equipment. The NBIC became a widely recognized complement to the ASME Code, especially for in-service equipment, as it offered guidance for maintaining ongoing safety throughout a pressure vessel’s lifecycle. This code has evolved in response to changes such as technological advancements and industry needs, reflecting NBBI’s commitment to continuous improvement.
The National Board also developed robust programs to support manufacturers and repair organizations through registration systems, quality assurance oversight, training courses, and technical resources. Its registration program established a centralized repository of pressure equipment data reports, enabling traceability and improving the ability of inspectors to monitor equipment safety history. This system significantly enhanced risk management for industries reliant on pressure technology.
Today, the National Board is still dedicated to promoting uniform safety standards, supporting inspector competency, and fostering collaboration among jurisdictions, manufacturers, and industry professionals. The organization continues to provide certifications, maintain the NBIC, conduct training, and offer technical guidance that strengthens the safety infrastructure of boilers and pressure vessels worldwide. Thanks to more than a century of expertise, the National Board plays a key role in advancing public safety and ensuring consistent oversight in industries that rely on high-pressure systems.
