NBBI In-Service Inspector (IS)

What is the primary purpose of the National Board Inspection Code (NBIC)?

• ATo design new boilers and pressure vessels
• BTo regulate the sale of pressure equipment
• CTo establish manufacturing standards for new construction
• DTo provide rules and guidelines for the installation, inspection, repair, and alteration…

Which part of the NBIC covers the requirements for periodic in-service inspections of boilers and pressure vessels?

• APart 1 — Installation
• BPart 4 — Pressure Relief Devices
• CPart 3 — Repairs and Alterations
• DPart 2 — Inspection

What are the two main types of in-service boiler inspections?

• AFabrication and erection inspections
• BHydrostatic and pneumatic inspections
• CInternal and external inspections
• DRadiographic and ultrasonic inspections

During an internal inspection of a firetube boiler, you observe thinning of the tube sheets around the tube holes. What is the most likely cause?

• ACorrosion caused by boiler water chemistry issues or galvanic action
• BNormal wear from steam flow
• CImpact damage from tube cleaning equipment
• DPaint peeling from the surface

What is the primary purpose of an in-service inspection of a pressure vessel?

• ATo assess the current condition and determine continued fitness for service at the operat…
• BTo verify the vessel meets original construction code requirements
• CTo redesign the vessel for higher pressure
• DTo determine the resale value of the vessel

Which of the following is the most common form of deterioration found during in-service inspections of boilers?

• AFatigue cracking
• BHydrogen embrittlement
• CGeneral corrosion and wastage
• DRadiation damage

What instrument is most commonly used to measure remaining wall thickness during in-service inspections?

• AA caliper
• BA ruler
• CAn ultrasonic thickness gauge
• DA pressure gauge

What is the minimum required thickness of a pressure vessel component?

• AThe thickness calculated using the original code of construction formulas for the current…
• BThe original as-built thickness minus the corrosion allowance
• CHalf of the original thickness
• DThe thickness determined by the manufacturer only

During an external inspection of an operating boiler, which of the following should the in-service inspector check?

• AOnly the boiler nameplate data
• BOnly the fuel supply
• CSafety valves, operating controls, low-water cutoffs, combustion conditions, piping conne…
• DOnly the electrical connections

What is the purpose of the low-water cutoff device on a steam boiler?

• ATo regulate the water flow rate into the boiler
• BTo control the steam quality
• CTo prevent overpressure conditions
• DTo shut down the burner if the water level drops below a safe minimum to prevent overheat…

What is ASME CSD-1?

• AA code for constructing new pressure vessels
• BControls and Safety Devices for Automatically Fired Boilers — a standard that specifies r…
• CA standard for chemical storage drums
• DA code for designing piping systems

What is pitting corrosion, and why is it particularly dangerous in pressure vessels?

• AUniform metal loss across the entire surface, easily detected
• BCorrosion caused only by external atmospheric exposure
• CSurface discoloration that does not affect structural integrity
• DLocalized corrosion creating small, deep holes that can penetrate the wall thickness rapi…

What is caustic embrittlement (caustic cracking) in boilers?

• AIntergranular cracking caused by the concentration of caustic (NaOH) in areas of high str…
• BA type of erosion caused by high-velocity steam
• CFatigue cracking from thermal cycling
• DCorrosion caused by acidic water

How often should safety valves on power boilers typically be tested?

• AEvery 10 years
• BOnly when there is a visible problem
• CAt intervals established by the jurisdiction, typically annually or at each certificate i…
• DEvery month

What is the purpose of NBIC Part 1 (Installation)?

• ATo provide rules for manufacturing new equipment
• BTo provide requirements for the proper installation of boilers, pressure vessels, and pip…
• CTo specify paint and insulation requirements only
• DTo establish employee training programs

What is a certificate inspection?

• AA jurisdictionally required periodic inspection to renew the operating certificate (permi…
• BAn inspection performed during manufacturing
• CAn inspection performed by the equipment manufacturer
• DAn inspection performed only at the request of the owner

What should the in-service inspector do FIRST when arriving at a site for an internal inspection of a boiler?

• AImmediately enter the boiler
• BBegin ultrasonic testing immediately
• CReview safety procedures, verify the boiler has been properly prepared (locked out, coole…
• DStart the boiler to observe it running

During an internal inspection, you find heavy scale deposits on the waterside of a watertube boiler. What concern does this raise?

• AThe boiler is operating too efficiently
• BScale acts as an insulator, reducing heat transfer and potentially causing overheating an…
• CScale improves the structural strength of the tubes
• DScale is normal and does not require attention

What is the difference between a repair and an alteration as defined by the NBIC?

• AThere is no difference
• BA repair restores equipment to safe operating condition per the original design; an alter…
• CA repair is more expensive than an alteration
• DAn alteration is performed without inspector involvement

Who may perform repairs and alterations to boilers and pressure vessels under the NBIC?

• AAny welding contractor
• BThe equipment owner using any available welder
• COnly organizations holding a valid National Board R Certificate of Authorization (R-stamp)
• DOnly the original manufacturer

What documentation is required after a repair or alteration is completed under the NBIC?

• ANo documentation is required
• BA National Board R-1 form (Report of Repair or Alteration) signed by the repair organizat…
• COnly a verbal report to the owner
• DA purchase receipt for materials used

What is oxygen pitting in boiler systems?

• ALocalized corrosion caused by dissolved oxygen in the boiler water attacking the metal su…
• BCorrosion caused by excessive alkalinity
• CErosion from high-velocity steam
• DStress corrosion cracking from hydrogen

What is the purpose of a pressure test after a repair involving welding on a pressure boundary?

• ATo clean the inside of the vessel
• BTo determine the new MAWP
• CTo verify the integrity of the repair weld and confirm that the repaired area can safely…
• DTo exercise the safety valves

An in-service inspector discovers a crack in the shell of a pressure vessel during a routine inspection. What is the first step?

• AImmediately condemn the vessel
• BIncrease the inspection frequency and continue operating
• CPaint over the crack to prevent further corrosion
• DRemove the vessel from service, investigate the cause, determine the extent of the crack…

What is the corrosion rate, and how is it calculated?

• AThe rate of metal loss over time, typically calculated by dividing the total metal loss b…
• BThe total amount of corrosion found during inspection
• CThe speed at which a chemical reaction occurs
• DThe cost of corrosion per year

How is the remaining life of a pressure vessel component estimated from thickness measurements?

• ABy dividing the available corrosion (current thickness minus minimum required thickness)…
• BBy visual appearance only
• CBy the vessel's age alone
• DBy the manufacturer's warranty period

What is the maximum allowable working pressure (MAWP) used for in the context of in-service inspection?

• ATo determine the resale value
• BOnly to mark on the nameplate
• CAs the reference pressure for calculating minimum required thickness, setting safety valv…
• DTo calculate the owner's insurance premium

What is re-rating of a pressure vessel?

• ARepainting the nameplate
• BReplacing the vessel with a new one
• CChanging the maximum allowable working pressure and/or temperature of a vessel based on i…
• DUpgrading the vessel's insulation

Which of the following conditions observed during an internal boiler inspection requires immediate attention?

• AMinor surface rust on the waterside
• BThrough-wall cracking or significant bulging of pressure parts
• CSlight discoloration of the fireside surfaces
• DMinor sediment accumulation in the mud drum

What is the primary safety concern when performing a confined space entry into a boiler for internal inspection?

• AAtmospheric hazards (oxygen deficiency, toxic gases, combustible atmosphere), engulfment,…
• BGetting the boiler dirty
• CBreaking inspection tools
• DMaking too much noise

What type of corrosion is characterized by metal loss in a narrow groove-like pattern along the waterline of a boiler?

• AGalvanic corrosion
• BGrooving corrosion (waterline attack)
• CPitting corrosion
• DErosion-corrosion

What NDE method would you use to determine the extent of a crack that has been found on the internal surface of a boiler drum?

• AMagnetic particle testing (MT) or liquid penetrant testing (PT) to define the crack lengt…
• BUltrasonic thickness measurement only
• CVisual examination only
• DRadiographic testing of the entire drum

What is erosion-corrosion in a boiler or pressure vessel?

• AAccelerated metal loss caused by the combined effects of corrosion and mechanical erosion…
• BCorrosion caused by stagnant fluid
• CCorrosion under insulation only
• DA type of fatigue cracking

What is the significance of finding bulging or distortion on a boiler tube during internal inspection?

• AIt is purely cosmetic
• BIt indicates the tube was manufactured incorrectly
• CIt means the tube is stronger than expected
• DIt indicates the tube has been overheated, possibly due to scale deposits, low water cond…

Under the NBIC, when is a pressure test required after a repair?

• AWhen the repair involves welding on the pressure boundary, unless the applicable code sec…
• BAfter every repair regardless of scope
• COnly when the owner requests it
• DNever, since the vessel was already tested during original construction

What is corrosion under insulation (CUI)?

• ACorrosion that occurs on the inside surface of a vessel due to water treatment
• BExternal corrosion of piping or vessels that occurs beneath thermal insulation due to moi…
• CErosion caused by insulation material rubbing against the vessel
• DInternal scaling due to high-temperature operation

What is the purpose of a safety relief valve on a hot water heating boiler (Section IV)?

• ATo regulate the water temperature
• BTo relieve pressure and/or temperature to prevent overpressure or overtemperature conditi…
• CTo drain the boiler for maintenance
• DTo control the flow rate

During an in-service inspection, you measure the wall thickness of a pressure vessel shell and find it is less than the calculated minimum required thickness at the current MAWP. What options are available?

• AContinue operating at the current MAWP
• BReplace only the nameplate with a lower pressure rating without engineering analysis
• CIncrease the safety valve set pressure to compensate
• DThe vessel must be repaired to restore wall thickness, re-rated to a lower MAWP that the…

What is hydrogen damage in boiler systems?

• ADamage caused by hydrogen used as a fuel
• BA loss of ductility and cracking caused by atomic hydrogen diffusing into the steel and r…
• CCorrosion caused by acidic water
• DErosion from high-velocity hydrogen gas

What is the purpose of a flame safeguard system on an automatically fired boiler?

• ATo regulate the flame color
• BTo increase combustion efficiency
• CTo monitor the burner flame and automatically shut down the fuel supply if the flame is n…
• DTo control the exhaust gas temperature

What does ASME B31.1 cover?

• ADesign of pressure vessels
• BNondestructive examination methods
• CHeating boiler construction
• DPower piping — rules for piping systems associated with power boilers and other high-pres…

During an inspection, you find that a pressure vessel's nameplate is missing. What should the inspector do?

• AIgnore it since the vessel is in service
• BAttempt to re-establish the vessel's identity through National Board records, original Ma…
• CCondemn the vessel immediately without further investigation
• DApply a new nameplate with estimated data

What welding qualification documents must an R-stamp holder maintain for welders performing repair work?

• ANo documentation is required
• BValid Welding Procedure Specifications (WPS) supported by Procedure Qualification Records…
• COnly a letter from the welder stating their experience
• DA vendor certificate from the welding electrode manufacturer

What is the difference between a jurisdictional inspector and an insurance company inspector?

• AThere is no difference in their authority
• BOnly jurisdictional inspectors can perform inspections
• CA jurisdictional inspector is employed by the government authority; an insurance company…
• DInsurance company inspectors have more authority

What type of cracking may develop in boiler tubes exposed to repeated thermal cycling?

• ACaustic cracking
• BCorrosion fatigue
• CHydrogen-induced cracking
• DThermal fatigue cracking

What information should be recorded in an in-service inspection report?

• AOnly the date and inspector's name
• BOnly a pass or fail result
• CEquipment identification, condition findings, thickness measurements, NDE results, defect…
• DOnly photographs

What is stress corrosion cracking (SCC)?

• ACracking caused by mechanical overload
• BCracking due to manufacturing defects
• CCracking caused by welding only
• DCracking that occurs under the combined action of tensile stress and a specific corrosive…