Reference · 59 terms

Inspection and TIC glossary

Plain-English definitions covering inspection methods, testing standards, and the procurement vocabulary that governs industrial vendor sourcing. Written for facility and procurement buyers who need the vocabulary before a first call.

Biosafety Cabinets 2

Biosafety Cabinet Class (Class I, II, III)

Biosafety cabinet class describes the level of protection an airflow-containment cabinet provides: personnel protection only (Class I), personnel plus product plus environmental protection (Class II, with sub-types such as A1, A2, B1, B2), or maximum gas-tight containment for highly infectious work (Class III), per standards including NSF/ANSI 49, which primarily governs Class II units in North America (EN 12469 is the corresponding European standard). A vendor quote for certification or repair should specify which class of cabinet is involved before pricing, since the applicable tests and pass criteria differ by class.

Face Velocity (Inflow Velocity)

Face velocity is the speed of air measured at the sash opening of a biosafety cabinet (where it is also called inflow velocity) or across a filter face, expressed in feet or meters per minute, with minimums set by standards such as NSF/ANSI 49 (for example roughly 75 ft/min for Class II Type A1 and 100 ft/min for Type A2 cabinets). An out-of-range face velocity reading is one of the most common reasons a cabinet fails certification, so buyers should confirm this measurement is explicitly included in a quoted certification scope.

Certification, hazardous area classification 1

IECEx

IECEx (the IEC System for Certification to Standards Relating to Equipment for Use in Explosive Atmospheres) is an international certification scheme established in 1996, built on the IEC 60079 series, and covering equipment, service facilities, and personnel competence for explosive atmospheres. Buyers sourcing hazardous-area equipment across borders should confirm the destination jurisdiction accepts IECEx outright or requires a local equivalent such as ATEX, since one certification does not automatically satisfy every regulator.

Cleanroom Classification 3

Differential Pressure / Pressure Cascade

Differential pressure is the measured air pressure difference, in pascals, between adjacent rooms or zones; a pressure cascade is the deliberate sequencing of these differences so each cleaner zone is held at higher pressure than the next, keeping airflow moving from cleaner to less-clean areas to limit cross-contamination. Buyers should ask whether an inspection covers cascade verification across the full sequence of connected rooms rather than a single room's reading against the corridor.

ISO Class (ISO 14644-1 Cleanroom Classification)

ISO 14644-1 is the international standard that rates a cleanroom's air cleanliness by the maximum allowable count of airborne particles at specified sizes, producing a rating such as ISO Class 5, 7, or 8. The same room can test into a different class depending on which occupancy state it was measured in, so a buyer should confirm both the classification method and the occupancy state stated on any report before comparing quotes.

Occupancy State (As-Built / At-Rest / Operational)

Occupancy state, as defined in ISO 14644-1, describes the condition of a cleanroom when particle counts are taken: as-built (construction complete, no equipment or people), at-rest (equipment installed and operating as agreed between customer and supplier, but no people present), or operational (normal production with equipment running and personnel present). Particle counts and the resulting ISO Class can differ meaningfully between states, so a classification report should always specify which state the data was collected in.

Codes and Standards 2

ASME Boiler and Pressure Vessel Code (BPVC)

The ASME Boiler and Pressure Vessel Code (BPVC) is the design and construction standard used across North America and internationally for boilers, pressure vessels, and related components, published in sections such as Section I (Power Boilers) and Section VIII (Pressure Vessels). For procurement, it matters because new equipment is built and stamped to a specific BPVC section and edition, and that stamp determines which post-construction codes, such as the NBIC, apply once the equipment is placed in service.

Related: Jurisdictional Inspector

NBIC (National Board Inspection Code)

The National Board Inspection Code (NBIC) sets rules for the installation, inspection, repair, and alteration of in-service pressure-retaining equipment and pressure relief devices, published in four parts, and it has been adopted into law by most US and Canadian jurisdictions. When a vessel or boiler needs a post-construction repair or alteration, the NBIC, not the original ASME BPVC used to build it, typically governs how that work must be performed and documented.

Related: Jurisdictional Inspector

Combustible dust, process safety 1

DHA (Dust Hazard Analysis)

A DHA is the systematic hazard assessment required by NFPA 652 to identify fire, flash-fire, and explosion risks from combustible particulate solids in a process or facility, covering the materials involved, the process hazards, and a resulting management plan. Most existing facilities faced a compliance deadline of September 7, 2020 for completing an initial DHA, which makes current DHA status a practical pre-qualification question for inspection and process safety vendors.

Combustible dust, testing 2

Kst/Pmax (Dust Explosion Severity Parameters)

Kst (the normalized maximum rate of pressure rise) and Pmax (the maximum explosion pressure) are the two core severity values produced by ASTM E1226 testing in a 20-liter chamber, and together they size venting, suppression, and isolation equipment for a given dust. These values vary by material and particle size, so a procurement spec should require test data for the actual dust handled rather than a generic industry figure.

MIE (Minimum Ignition Energy)

MIE is the lowest spark energy, determined by standardized tests such as ASTM E2019, capable of igniting a dispersed dust cloud. A low MIE value means static discharge or minor sparking can trigger ignition, so procurement should confirm that grounding, bonding, and inerting controls on quoted equipment were sized against the material's actual measured MIE rather than an assumed value.

Consumable, UT accessory 1

Couplant

Couplant is the gel, water, or oil-based fluid applied between an ultrasonic transducer and the test surface to remove the air gap that would otherwise block sound transmission into the material. Couplant choice affects field productivity on hot, vertical, overhead, or rough-surface work, so buyers scoping UT in those conditions should ask the vendor which couplant they plan to use rather than assuming a generic gel will work.

Containment Testing 2

Filter Integrity Test (PAO/DOP Test)

Filter integrity testing is an in-situ leak test in which a challenge aerosol, historically DOP (dioctyl phthalate) and now generally PAO (poly-alpha olefin) after toxicological concerns identified DOP as a suspected human carcinogen, is introduced upstream of an installed HEPA or ULPA filter while a photometer scans the downstream face for leaks, following methods described in ISO 14644-3. Buyers should ask which aerosol a vendor uses and confirm the scan is performed against the acceptance criteria in the applicable standard, since this test is a core deliverable in most cleanroom and cabinet certification contracts.

KI-Discus Test (Operator Protection Factor Test)

The KI-Discus test, defined in EN 12469, measures how much aerosol escapes from a biosafety cabinet's front opening by releasing a potassium iodide mist inside the cabinet and analyzing collector filters outside it, producing an operator protection factor rather than a filter leak reading. This is a distinct deliverable from a HEPA filter integrity test and is not always bundled into a standard annual certification quote, so buyers who need documented containment performance should confirm it is scoped and priced separately.

Electrical Safety Testing 2

Dielectric Withstand Test

A dielectric withstand test applies a voltage well above normal operating levels across a component's insulation for a set duration to confirm the insulation can block current without breaking down. Procurement specs should state the exact applied voltage, duration, and pass/fail leakage-current threshold in writing, since the term covers more than one method (AC or DC) that are not interchangeable in their results.

Hipot Test

Hipot, short for high potential, is the common working name for a dielectric withstand test, typically a single go/no-go check on new or repaired equipment to confirm the insulation survives a voltage spike without breakdown. It differs from an insulation resistance test performed with a megohmmeter, which trends insulation quality in ohms over time rather than pass/fail at one high-voltage event, so a procurement spec should say plainly which of the two is required.

Exposure limits, industrial hygiene 6

Exposure Monitoring

Exposure monitoring measures a worker's actual airborne exposure, most commonly through personal breathing-zone air sampling worn by the employee, as distinct from fixed-area sampling, collected over a period meant to approximate a full shift for comparison against the applicable PEL or TLV. A procurement scope for industrial hygiene services should specify personal versus area sampling, the averaging period, and which limit the vendor is sampling against, since those choices change both cost and the defensibility of the results.

IDLH (Immediately Dangerous to Life or Health)

An IDLH concentration, as defined by NIOSH, is an airborne exposure level likely to cause death, irreversible harm, or prevent escape, and current guidance applies no allowable exposure duration at that level. Procurement teams evaluating confined-space or emergency-response vendors should verify IDLH monitoring practices and supplied-air respiratory protocols before award, since this is a life-safety threshold rather than a routine compliance figure.

PEL (Permissible Exposure Limit)

A PEL is the legally enforceable airborne exposure ceiling that OSHA sets under 29 CFR 1910.1000 for a specific chemical or physical agent, usually expressed as an 8-hour time-weighted average. Many current PELs date to the early 1970s and have not been updated since, so a vendor citing PEL compliance is meeting the legal floor, not necessarily the most protective limit available.

STEL (Short-Term Exposure Limit)

STEL caps a worker's average exposure to a substance over a 15-minute window, generally limited to four occurrences per shift with at least 60 minutes between them, even when the 8-hour average stays within limits. When reviewing a monitoring proposal, confirm it captures short, high-intensity tasks such as batch charging or tank entry, not only full-shift averages.

TLV (Threshold Limit Value)

TLV is a health-based airborne exposure guideline published annually by ACGIH, a private professional association rather than a government regulator, covering roughly 600 substances and expressed as TLV-TWA, TLV-STEL, or TLV-C (ceiling). It is not legally enforceable the way an OSHA PEL is, but industrial hygiene scopes of work often specify TLV compliance as the stricter benchmark when the applicable PEL is outdated.

TWA (Time-Weighted Average)

TWA is the averaging method behind most PELs and TLVs, calculating a worker's exposure across a defined period, typically 8 hours, so brief peaks are balanced against lower-exposure stretches. When comparing exposure-monitoring proposals, confirm the sampling duration and averaging period actually match what the cited PEL or TLV requires.

Filtration 2

HEPA Filter

HEPA (High-Efficiency Particulate Air) filter is a filter tested and rated to remove at least 99.97% of particles at 0.3 microns, the size range filters find hardest to capture, under the North American IEST test method (IEST-RP-CC001); European EN 1822 uses a related but separately tiered efficiency classification (EPA, HEPA H13/H14, ULPA) based on each filter's actual most-penetrating particle size rather than a fixed 0.3-micron figure. Because "HEPA" is a performance standard rather than a single universal spec sheet, buyers should ask a vendor which test standard and certified efficiency figure backs a given filter.

ULPA Filter

ULPA (Ultra-Low Penetration Air) filter is a higher-efficiency filter class, standardized under IEST-RP-CC001 (currently in its 7th edition, IEST-RP-CC001.7), rated to remove at least 99.999% of particles at their most penetrating size, used where a room's required ISO Class calls for tighter particle control than HEPA provides. Buyers should confirm whether the facility's actual classification target requires ULPA-grade filtration, since ULPA units cost more to procure, install, and integrity-test than HEPA.

Hazardous area classification 2

ATEX Zone

ATEX (from the French Atmosphères Explosibles) is the EU framework, currently Directive 2014/34/EU, for classifying areas where explosive gas or dust atmospheres may form. Gas and vapor hazards are ranked Zone 0, 1, or 2 and dust hazards Zone 20, 21, or 22 by how continuously the explosive atmosphere is present, and equipment sourced for a given zone must carry the matching protection category before a vendor can quote compliant hardware.

Hazardous Area Classification (Class/Division vs. Zone)

Hazardous area classification maps a facility by the likelihood and duration of flammable gas, vapor, or dust presence, using either the Class/Division/Group system under NEC Article 500 (the US standard; Canada runs a parallel Class/Division system under its own Canadian Electrical Code, CSA C22.1, not the NEC itself) or the Zone system under NEC Articles 505 and 506, which aligns with IEC and ATEX practice used in most other countries. The two systems cannot be mixed within a single installation, so a procurement spec must state which system applies before a vendor can propose compliant equipment.

Infrastructure Inspection / Nondestructive Testing 1

Nondestructive Examination / Testing (NDE/NDT)

NDE, also called NDT, is any inspection method, such as ultrasonic, radiographic, magnetic particle, or dye penetrant testing, that evaluates a material or component for cracks, corrosion, or other flaws without damaging or altering it. Procurement specs should name the specific NDE method and the acceptance standard, for example an ASME or AWS code, rather than the generic term, since methods vary widely in the flaw types and sizes they can actually detect.

Infrastructure Inspection / Regulatory 1

NBIS (National Bridge Inspection Standards)

NBIS is the federal regulatory framework, codified at 23 CFR 650 Subpart C and administered by the Federal Highway Administration, that sets minimum requirements for inspecting highway bridges on public roads in the US, covering inspector qualifications, inspection frequency, and reporting. Buyers sourcing bridge inspection services should confirm a vendor's inspectors and program currently meet NBIS qualification and frequency requirements, since a noncompliant inspection can put the bridge owner out of compliance with federal reporting obligations.

Infrastructure Inspection / Structural 1

Fracture-Critical Member (FCM)

A fracture-critical member is a steel bridge component in tension whose failure would likely cause part or all of the bridge to collapse, because the structure provides no redundant load path to compensate. FHWA's 2022 Specifications for the National Bridge Inventory has shifted preferred terminology toward nonredundant steel tension member (NSTM), so buyers should confirm which term a vendor's inspection scope and contract use before comparing bids.

Inspection Methodology 1

RBI (Risk-Based Inspection)

Risk-Based Inspection (RBI), as defined in API RP 580, is a methodology that sets inspection frequency and scope for pressure vessels, piping, storage tanks, and related equipment according to the probability and consequence of failure, rather than fixed calendar intervals. Facilities running an RBI program expect vendors to justify inspection plans against a documented risk ranking, so a vendor's proposal should show how its findings and intervals map back to that risk basis.

Inspector Certifications 3

API 510 (Pressure Vessel Inspection Code)

API 510 is the American Petroleum Institute code governing in-service inspection, repair, alteration, and rerating of pressure vessels such as reactors, drums, and towers. When sourcing inspection for vessels already in operation, confirm the inspector holds a current API 510 certification, since it is scoped to in-service fitness-for-service and inspection interval work rather than new construction.

API 570 (Piping Inspection Code)

API 570 covers in-service inspection, repair, alteration, and rerating of metallic and non-metallic process piping systems, including corrosion monitoring and thickness measurement. It is a distinct credential from vessel work (API 510) or storage tank work (API 653), so a piping integrity scope of work should specify it by name.

API 653 (Tank Inspection Code)

API 653 governs the inspection, repair, alteration, and reconstruction of in-service welded steel above-ground storage tanks. Tank floors, shells, and roofs have inspection intervals and evaluation methods distinct from pressure vessels or piping, so buyers sourcing tank inspection work should verify API 653 certification specifically rather than a general pressure equipment credential.

NDT method, advanced volumetric 1

Phased Array Ultrasonic Testing (PAUT)

Phased array ultrasonic testing uses a probe made of many small elements fired in a controlled sequence to steer and focus the sound beam electronically, producing a cross-sectional image of the weld or material rather than a single signal trace. It typically costs more per exam than conventional UT but provides a permanent, reviewable image record, so buyers comparing quotes should confirm whether a line item labeled "UT" is conventional or phased array before comparing prices across vendors.

NDT method, global monitoring 1

Acoustic Emission Testing (AE)

Acoustic emission testing places an array of sensors on a structure and listens for the transient elastic waves released when a growing crack, leak, or active corrosion process releases energy, typically while the vessel, tank, or pipeline is under load during a pressure test. Unlike UT, MT, PT, RT, or VT, which are point-in-time spot checks, AE monitors the whole structure at once during the loading event and flags active sources for follow-up examination by another method rather than sizing the flaw directly.

NDT method, measurement 1

Ultrasonic Thickness Gauging (UTG)

Ultrasonic thickness gauging is a focused application of ultrasonic testing that measures remaining wall thickness at a single point, used to track corrosion or erosion loss in piping, tanks, and pressure vessels over time. Because each reading is a spot measurement, a procurement scope should specify the grid density or number of corrosion monitoring locations (CMLs), since a sparse grid can miss localized pitting between measurement points.

NDT method, surface 2

PT (Liquid Penetrant Testing)

Liquid penetrant testing, also called dye penetrant testing, applies a low-viscosity dye to a cleaned surface, allows it to seep into surface-breaking discontinuities, then draws it back out with a developer so flaws appear as visible or fluorescent indications. It works on any nonporous material regardless of magnetic properties, but it only detects discontinuities open to the surface, so it cannot find subsurface flaws the way UT or RT can.

VT (Visual Testing)

Visual testing is the direct or remote examination of a surface, weld, or component for visible conditions such as cracks, corrosion, misalignment, or weld profile defects, using the unaided eye or magnification and adequate lighting, or a borescope or camera for inaccessible areas. VT is usually the first and least expensive inspection performed on a job and is often a prerequisite check before a vendor applies a more sensitive method such as MT, PT, UT, or RT.

NDT method, surface and near-surface 1

MT (Magnetic Particle Testing)

Magnetic particle testing magnetizes a ferromagnetic part and applies fine iron particles that collect at surface and near-surface cracks, making them visible as indications. It only works on magnetic materials such as carbon and low-alloy steel, so buyers sourcing inspection for non-magnetic metals like austenitic stainless steel or aluminum should expect the vendor to recommend liquid penetrant or eddy current testing instead.

NDT method, surface and near-surface (electromagnetic) 1

Eddy Current Testing (ECT)

Eddy current testing induces alternating electrical currents in a conductive material through a coil and measures how surface and near-surface flaws, conductivity changes, or coating thickness disturb those currents. It works only on electrically conductive materials and needs no couplant or consumables, but its penetration depth is limited compared to UT or RT, so buyers should confirm ECT is appropriate for the flaw depth and material before specifying it, for example on heat exchanger tubing or aircraft skin.

NDT method, volumetric 2

RT (Radiographic Testing)

Radiographic testing passes X-rays or gamma rays through a component onto film or a digital detector to produce an image showing internal voids, porosity, or inclusions by density difference. Because RT uses ionizing radiation, it requires radiation-safety controls such as exclusion zones and shielding and often has to be scheduled around production downtime, which typically makes it slower and more expensive per weld than UT.

UT (Ultrasonic Testing)

Ultrasonic testing sends high-frequency sound waves into a material through a transducer and reads the reflected signal to locate internal flaws such as cracks, lack of fusion, or inclusions, and to measure remaining wall thickness. Buyers should confirm whether the vendor is quoting conventional single-probe UT or phased array UT, since the technique and reference standard used affect what size flaw the exam can reliably detect.

Related: Couplant

Personnel and Credentials 1

Jurisdictional Inspector

A jurisdictional inspector is an individual who holds a National Board commission and the endorsement required by the applicable state, provincial, or other governing jurisdiction to perform legally mandated inspections of boilers and pressure vessels, whether during original construction (as an Authorized Inspector employed by an Authorized Inspection Agency) or once in service (as a Commissioned Inspector). Because commission and endorsement requirements are set jurisdiction by jurisdiction, procurement teams should confirm a vendor's inspectors are properly commissioned for both the equipment type and the specific state or province where the equipment operates.

Personnel qualification 1

NDT Personnel Certification (Level I, II, III)

NDT technicians are qualified to Level I, II, or III within a specific method such as UT, MT, PT, RT, VT, or eddy current, with the top level representing the highest qualification, able to write procedures, interpret results, and train other technicians. Certification is most commonly administered in the US through employer-based programs following ASNT's SNT-TC-1A recommended practice or the ANSI/ASNT CP-189 standard (both use Roman numerals, Level I/II/III), or internationally through third-party certification under ISO 9712, which instead uses Arabic numerals (Level 1/2/3) and is the only one of the three that defines a Level 1 tier. A buyer's RFP should state which scheme and level it requires for the method being purchased rather than assuming all vendor certifications, or level labels, are equivalent.

Process Safety 4

HAZOP (Hazard and Operability Study)

HAZOP is a structured, qualitative technique for conducting a PHA that applies guide words, such as no, more, less, and reverse, to process parameters like flow, pressure, and temperature to systematically identify deviations from design intent and their causes and consequences. It is one of several accepted PHA methodologies, so a scope of work should name HAZOP explicitly rather than assume it is the default.

LOPA (Layer of Protection Analysis)

Layer of Protection Analysis (LOPA) is a semi-quantitative risk assessment method, developed and published by the Center for Chemical Process Safety (CCPS), that evaluates one cause-and-consequence scenario at a time to check whether the independent protection layers already in place reduce risk enough, or whether more safeguards are needed. LOPA is commonly scoped as a follow-on study after a HAZOP flags a scenario for closer review, so it should be priced and scoped as a separate line item rather than assumed to be included in HAZOP work.

Mechanical Integrity (MI)

Mechanical Integrity (MI) is the OSHA PSM element under 29 CFR 1910.119(j) requiring written procedures, training, and documented inspection and testing intended to keep covered process equipment, such as pressure vessels, piping, relief devices, and emergency shutdown systems, reliable throughout its service life. MI programs are expected to follow RAGAGEP (recognized and generally accepted good engineering practices), meaning named industry codes from bodies like API and ASME, so a vendor's inspection scope and reports should reference the specific code being followed rather than an internal-only standard.

PHA (Process Hazard Analysis)

A Process Hazard Analysis (PHA) is a systematic, team-based review that identifies the hazards of a process and evaluates the safeguards controlling them; OSHA PSM requires PHAs to be revalidated at least every five years. When sourcing a PHA facilitator, confirm which methodology is proposed, such as HAZOP, what-if, or checklist analysis, since PHA is the umbrella requirement and not a single fixed technique.

Procurement 1

Request for Proposal (RFP)

An RFP is a procurement document that describes a buyer's project or need and asks vendors to propose both their approach and their price, giving suppliers latitude to design a solution rather than quote against a fixed spec. It differs from a request for quotation (RFQ), which asks only for price against a spec the buyer has already defined, so an inspection buyer should use an RFP when the method or standard to be applied is still open for the vendor to propose.

Related: Inspection and Test Plan (ITP)

Regulatory Framework 1

PSM (Process Safety Management)

Process Safety Management (PSM) is the OSHA regulatory framework under 29 CFR 1910.119 that requires facilities handling specific highly hazardous chemicals above threshold quantities to manage the risk of a catastrophic release through 14 defined program elements, including process hazard analysis and mechanical integrity. Buyers should know PSM applicability drives which inspection, testing, and documentation obligations a facility must meet, and vendors supporting PSM-covered sites should be able to name which element their scope of work supports.

Requalification and Monitoring 2

Periodic Monitoring (ISO 14644-2)

ISO 14644-2 governs the ongoing monitoring plan a facility uses to show continued compliance with its classified air cleanliness between full requalifications, covering which parameters to monitor and at what frequency, based on a risk assessment rather than a single fixed calendar (the standard's own default reclassification interval is 12 months for ISO Class 6 and cleaner rooms.. wait

Requalification

Requalification is the scheduled retesting of a cleanroom, biosafety cabinet, or containment system to confirm it still meets its original classification or certification, performed at a defined interval and also triggered by events such as relocation, filter replacement, or repair. Buyers should get both the routine interval and the event-based triggers in writing, since a lapsed requalification is generally treated by auditors and granting agencies as equivalent to having no certification at all.

TIC Industry 1

TIC Industry (Testing, Inspection, and Certification)

TIC refers collectively to testing, inspection, and certification services that confirm products, installations, and processes meet a specified standard, regulation, or contract requirement, with testing measuring performance, inspection checking conformity, and certification issuing formal proof of compliance. Buyers sourcing from this sector should treat the three functions as distinct deliverables, since a firm that tests and inspects an item and also certifies it can create an independence conflict under accreditation rules such as ISO/IEC 17020.

TIC Industry / Accreditation 1

ISO/IEC 17020 Inspection Body

ISO/IEC 17020 is the international standard accreditation bodies use to assess whether an inspection company is competent, consistent, and impartial. The prior (2012) edition classified inspection bodies as type A, fully independent, or type B or C, which had a lesser degree of separation from the design, manufacture, or sale of what they inspect; ISO/IEC 17020:2026, published March 27, 2026 (the day the 2012 edition was withdrawn), collapses that three-way split into type A and type non-A. Accreditation issued under the 2012 edition stays valid only until March 27, 2029, so a vendor may still cite a legacy A/B/C designation during that transition window. When comparing third-party inspectors, buyers should ask which type applies, which edition the accreditation was assessed against, and confirm current accreditation status directly with the accrediting body rather than relying on the vendor's own claim.

TIC Industry / Calibration 1

Calibration Traceability

Calibration traceability means a test instrument's measurement result can be linked, through an unbroken documented chain of calibrations, back to a national or international measurement standard, which in the US is typically NIST. When a contract requires NIST-traceable or ISO/IEC 17025-accredited calibration, it is the calibration laboratory's documented competence and traceability that is being certified, not just the instrument itself.

TIC Industry / Procurement 3

Hold Point / Witness Point

A hold point is a mandatory stop in an inspection and test plan where work cannot legally proceed until the designated inspector formally releases it, while a witness point is a notified checkpoint the inspector is invited to observe but where work may continue on schedule if they do not attend. Buyers should specify in the contract which checkpoints are hold points versus witness points, since treating a hold point as a witness point removes the buyer's leverage to stop nonconforming work before it continues.

Inspection and Test Plan (ITP)

An ITP is a project document that lists, in sequence, every inspection and test a piece of work or equipment must pass, who performs it, which standard it is checked against, and what record proves it happened. Procurement should require the ITP, including its hold points and witness points, to be agreed before work starts rather than submitted afterward, since it is the paper trail buyers rely on to enforce acceptance criteria.

Third-Party Inspection (TPI)

Third-party inspection is verification performed by an inspection company that is independent of both buyer and seller, confirming that purchased equipment, materials, or work meet contract specifications and applicable codes before or during shipment. Under ISO/IEC 17020, an inspection body must stay separate from the design, manufacturing, or sales activity on the item it inspects to remain impartial, which is what buyers are relying on when they specify TPI instead of accepting a supplier's self-reported quality data.

Umbrella term 1

NDT (Nondestructive Testing)

Nondestructive testing is the umbrella term for inspection methods that evaluate a material, weld, or component for flaws without cutting into it or removing it from service. For a buyer, NDT is a category on a scope of work rather than a single deliverable, so a vendor quote should name the specific method or combination of methods (UT, MT, PT, RT, VT, eddy current, acoustic emission) that will actually be performed.

Inspection vendor sourcing brief

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