NBBI Authorized Inspector (AI) cheat sheet

Section I applies to power boilers generating steam above 15 psig and hot-water boilers operating above 160 psig or 250°F, including fired and unfired steam boilers and certain economizers.

Section IV applies to heating boilers limited to 15 psig steam or 160 psig water at 250°F; it covers cast-iron and steel heating boilers and their appurtenances.

Section VIII Div 1 applies to pressure vessels with internal or external pressure exceeding 15 psi; Div 2 provides alternative rules with design-by-analysis and higher allowable stresses; Div 3 covers high-pressure vessels.

Section I allowable stress values in Section II Part D are based on minimum tensile strength divided by 3.5 and yield strength divided by 1.5, limited by temperature.

Section VIII Div 1 joint efficiency for Type 1 butt welds is E = 1.00 with full radiography, 0.85 with spot radiography, and 0.70 with no radiography.

Section I hydrostatic test pressure is 1.5 × MAWP; Section VIII Div 1 test pressure is 1.3 × MAWP × (allowable stress at test temperature / allowable stress at design temperature).

Section I requires safety valve capacity to prevent pressure from exceeding 110% of MAWP; the set pressure may not exceed MAWP.

Section IV heating boilers are stamped with the H symbol; Section I power boilers use the S symbol; Section VIII Div 1 vessels use the U symbol.

NBIC Part 2 covers in-service inspection of boilers and pressure vessels; it describes inspection methods, inspector qualification, condition evaluation, and records review.

NBIC does not set a universal inspection interval; the jurisdiction or owner/user establishes intervals based on service conditions, inspection history, and risk.

An NBIC inspection includes review of nameplate and data report, external examination, internal examination when required, safety-valve verification, and records review.

The inspector evaluates defects against NBIC acceptance criteria; cracks, laminations, and corrosion may require repair, alteration, or rerating.

NBIC Part 3 governs repairs and alterations; Part 4 covers heating boilers.

NBIC requires that repairs and alterations be performed by holders of an R Certificate of Authorization and documented on an R-1 form.

For pressure vessels, NBIC inspection may include visual examination, ultrasonic thickness measurement, and other NDE methods selected by the inspector.

A boiler or pressure vessel that fails NBIC inspection may be removed from service until repaired and reinspected.

A repair restores a boiler or pressure vessel to a condition that meets the original Code; an alteration changes MAWP, design temperature, or other design parameters.

Any repair or alteration to a Code item requires an R Certificate of Authorization holder and an R-1 form signed by the inspector.

Changing the MAWP or maximum temperature requires an alteration, new calculations, and a new or supplemental nameplate.

Repair welds must be made under a WPS/PQR qualified per Section IX, and welders must be qualified for the process and position.

NDE of repair welds is generally required to the extent that the original joint required it, or as specified by the inspector.

The original nameplate is retained; an alteration nameplate marked with the R symbol shows the new MAWP and temperature.

Repairs to pressure relief valves require a VR Certificate of Authorization and valve repair documentation.

Post-weld heat treatment after a repair is required when the original Code or material thickness required it.

ASME Section II Part A lists ferrous material specifications, Part B nonferrous, Part C welding materials, and Part D allowable stresses and physical properties.

Materials used in Code construction must conform to an ASME specification listed in Section II; unlisted materials require a Code Case or special approval.

Material Test Reports must be traceable to the heat number and to the specific item; the inspector reviews MTRs for compliance.

Section IX groups base metals by P-number and welding materials by F-number and A-number for procedure qualification.

Impact testing requirements depend on material, thickness, and temperature; Section VIII Div 1 UCS-66 provides exemption curves.

Section I and Section VIII allow certain materials only within specified temperature ranges; the allowable stress tables show these limits.

Marking of materials must be maintained or transferred; stamps or tags identify specification and heat number.

Section IX requires a written WPS supported by a PQR; essential variables include process, P-number, thickness, position, and preheat.

Welder performance qualification must be per Section IX and remains valid only while the welder uses the process at least once every six months.

Section VIII Div 1 full radiography acceptance is in UW-51; spot radiography acceptance is in UW-52.

NDE personnel must be qualified per ASNT SNT-TC-1A or CP-189, or an equivalent program accepted by the Code.

Joint efficiency depends on weld type and extent of radiography; Type 1 full radiography gives E = 1.00 in Section VIII Div 1.

Visual examination of welds is required before and after NDE; welds must be free of cracks, undercut beyond limits, and unacceptable porosity.

Hydrostatic testing after welding is required unless the Code provides an exemption; the inspector witnesses the test and checks gauge calibration.

Section I has specific radiographic requirements for longitudinal and circumferential butt welds in drums and shells.

A safety valve is a pressure relief valve actuated by inlet static pressure and characterized by pop action; a relief valve opens proportionally.

ASME V symbol stamps safety valves for Section I; HV for Section IV heating boilers; UV for Section VIII pressure relief valves.

A National Board VR Certificate of Authorization is required to repair and remanufacture pressure relief valves.

Set pressure is the inlet pressure at which the valve begins to open; accumulation is the pressure increase above MAWP during discharge.

Section I limits accumulation to 110% of MAWP and requires the safety valve set pressure not to exceed MAWP.

Section VIII Div 1 limits accumulation to 110% of MAWP for a single relief valve and 116% for multiple valves.

Capacity certification of relief valves is based on National Board flow test requirements; valve capacity must equal or exceed the required relieving capacity.

Blowdown is the difference between set pressure and reseat pressure, expressed as a percentage of set pressure.

The Authorized Inspector verifies Code compliance throughout construction, including design review, material verification, welding, NDE, heat treatment, and testing.

The AI has authority to reject nonconforming work and to require repairs before Code stamping.

Before stamping, the AI confirms that all required inspections and tests are complete, data reports are signed, and nameplate data are correct.

The AI reviews WPS/PQR, welder qualifications, MTRs, NDE reports, heat-treatment records, and hydrostatic test records.

The AI witnesses hydrostatic tests, checks gauge calibration and test pressure, and verifies hold time.

For boilers, the AI verifies safety-valve capacity, set pressure, and accumulation limits.

The AI must be commissioned by the National Board and employed by an ASME-accredited Authorized Inspection Agency.

Section VIII Div 1 uses Form U-1 for pressure vessels; Div 2 uses U-2; Div 3 uses U-3.

Section I power boilers use Form P-2; Section IV heating boilers use Form H-2.

The Manufacturer's Data Report is signed by the manufacturer and the Authorized Inspector and includes design, material, NDE, and test data.

NBIC repairs and alterations are documented on Form R-1, signed by the R stamp holder and the inspector.

Data reports must not be signed before all required inspections and tests are complete; blank or incomplete forms are not acceptable.

Records must be retained and made available to the jurisdiction and inspector; the owner/user maintains inspection records.

The data report identifies the Code symbol stamp, MAWP, design temperature, and applicable Code edition and addenda.

ASME Code symbol stamps include S for Section I power boilers, H for Section IV heating boilers, U for Section VIII Div 1, U2 for Div 2, and U3 for Div 3.

Use of an ASME Code symbol stamp requires a valid Certificate of Authorization and an approved quality control manual.

Stamping and nameplate attachment are performed only after the Authorized Inspector authorizes the work.

The nameplate must show manufacturer, serial number, MAWP, design temperature, year built, and Code symbol.

NBIC R stamp is required for repairs and alterations; VR stamp is required for pressure relief valve repairs.

ASME Certificates of Authorization are renewed through audits by ASME; loss of certification prohibits stamping.

The Authorized Inspector's commission is issued by the National Board and must be maintained current.