The language behind engineering and construction.
148 terms across five connected fields.
Search the complete glossary or move through the five source clusters. Supplemental process-safety terms remain available alongside the document vocabulary.
148 terms
Cluster A: Cost and estimating
Cost and estimating
Preconstruction
The phase of a capital project between the decision to invest and the start of physical work, in which the design is developed, costs are estimated, permits are obtained and the contracting strategy is decided.
Read definitionCost estimate
A forecast of the probable cost of a defined scope of work, produced at a specific level of design maturity and valid only for that scope, that maturity and that point in time.
Read definitionBill of Quantities (BOQ)
A structured list of every item of work and material required for a project, with measured quantities, used as the basis for tendering and for valuing work as it is completed.
Read definitionQuantity take-off
The process of measuring and counting the quantities of work and materials in a project directly from its drawings, models and specifications.
Read definitionMaterial take-off (MTO)
A structured list of the physical materials — pipe, fittings, valves, structural steel, cable and similar — required to build a design, extracted from engineering drawings and models to drive procurement and estimating.
Read definitionUnit rate
The cost of one measured unit of a work item — one cubic metre of concrete placed, one metre of pipe welded — combining labour, materials, equipment, overheads and margin.
Read definitionSchedule of rates
A pre-agreed list of unit rates for defined work items, without quantities, used to price work whose extent is not known in advance.
Read definitionCost catalog
A maintained library of reference cost data — unit rates, resource norms, assemblies and material prices — from which estimates are built and against which bids are checked.
Read definitionCost breakdown structure (CBS)
A hierarchical structure that organises all project costs into defined categories, so that estimates, budgets and actuals can be compared at the same levels.
Read definitionWork breakdown structure (WBS)
A hierarchical decomposition of the total scope of a project into progressively smaller pieces of work, forming the common skeleton for scheduling, estimating and reporting.
Read definitionDirect costs
Costs that can be attributed to a specific, measurable item of permanent work — the labour, materials and equipment time consumed in building it.
Read definitionIndirect costs and overheads
Costs required to deliver the project that cannot be attributed to any single item of work — site management, temporary facilities, equipment fleets, insurances and the contractor's share of head-office cost.
Read definitionPreliminaries
The section of a tender or bill of quantities that prices the contractor's general obligations and site-wide costs — establishment, management, temporary works, insurances — separately from the measured work items.
Read definitionContingency
An amount included in an estimate or budget to cover costs that are expected to occur within the defined scope but cannot yet be itemised — the known-unknowns of the project.
Read definitionCost escalation
The anticipated change in prices between the date of an estimate and the dates when the work will actually be bought and built, provided for as a distinct line in the estimate.
Read definitionValue engineering
A structured review of a design against the functions it must perform, seeking ways to deliver the same function at lower whole-life cost — as distinct from simply cutting scope or quality.
Read definitionOrder-of-magnitude estimate
A screening-level cost estimate produced from minimal project definition, used to decide whether an idea deserves further study rather than to set a budget.
Read definitionDefinitive estimate
A high-maturity cost estimate built from substantially complete engineering and detailed take-offs, accurate enough to serve as the project's control budget and the basis for final investment commitment.
Read definitionBase estimate
The estimated cost of the defined scope at current prices, before contingency, escalation and reserves are added — the "what we can see, at today's money" figure.
Read definitionCost norm
A standardised statement of the resources — labour hours, materials, machine time — required to perform one unit of a defined work item, used as the objective core of an estimate.
Read definitionElemental cost plan
A cost plan organised by the functional elements of a building — substructure, frame, envelope, services — rather than by trades or materials, used to steer design toward a budget.
Read definitionCost benchmarking
Comparing a project's estimated or actual costs against a reference set of completed projects, normalised for size, location, time and scope, to test whether the numbers are reasonable.
Read definitionBudget vs estimate
An estimate is a prediction of what a scope of work will probably cost; a budget is a decision about how much money is allocated to it — related, but not the same number and not the same act.
Read definitionAACE estimate classes
A widely used framework, published by AACE International, that classifies cost estimates from Class 5 to Class 1 according to the level of project definition behind them and the accuracy that can honestly be expected.
Read definitionFactored estimate
An early estimating method for process plants in which total installed cost is derived by multiplying the cost of major equipment by empirically established factors.
Read definitionParametric estimating
Estimating cost from statistical relationships between cost and measurable project parameters — cost per square metre, per tonne of capacity, per kilometre — derived from historical data.
Read definitionAllowance
An amount included within the base estimate for an item that is known to be required but not yet defined in enough detail to measure — priced by judgement rather than take-off.
Read definitionProvisional sum
A stated amount included in a tender or contract for work that cannot be adequately defined at tender time, to be replaced by the actual cost of that work once it is instructed and done.
Read definitionMTO growth allowance
A percentage added to the measured quantities of a material take-off to cover the growth expected between the current design stage and the final installed quantities.
Read definitionBulk materials and tagged items
The two categories every engineering material list divides into: tagged items, specified and tracked individually by tag number, and bulk materials, specified by class and counted in aggregate.
Read definitionTotal installed cost (TIC)
The full cost of delivering an operating asset — equipment, bulk materials, construction labour, indirects, engineering and project services — as distinct from the cost of the equipment alone.
Read definitionCluster B: Design, permitting and approval
Design, permitting and approval
Design documentation
The complete set of drawings, specifications, calculations, schedules and reports that defines what is to be built, produced in stages by the design organisation and consumed by everyone else on the project.
Read definitionPermitting package
The specific subset of project documentation assembled and formatted for submission to an authority in order to obtain a permit or approval.
Read definitionBuilding permit
The formal authorisation issued by a competent authority that allows construction of a defined project to begin, granted after the authority has reviewed the submitted documentation.
Read definitionDesign review
A structured examination of design outputs against requirements, codes and project criteria at a defined point, carried out to catch errors and misalignments while they are still cheap to fix.
Read definitionState examination (State Expertise)
A mandatory expert review of a project's design documentation — and in most such systems its cost estimates — by a state or state-accredited body, whose positive conclusion is a precondition for a construction permit.
Read definitionCode compliance check
The verification that a design satisfies the requirements of the codes, standards and regulations that apply to it, traced clause by clause to the documents that demonstrate compliance.
Read definitionCompleteness check
A verification that a documentation set contains everything it is required to contain — every document, section, attachment, signature and form — performed before any substantive review begins.
Read definitionSubmittal
A document, drawing, sample or product datasheet that a contractor sends to the design team for review and approval before the associated material is procured or the work executed.
Read definitionNon-conformance report (NCR)
A formal record that work, material or documentation has been found not to conform to the specified requirements, together with the decision on what to do about it.
Read definitionRequest for information (RFI)
A formal written question from the contractor to the design team asking for clarification, missing information or resolution of a conflict in the contract documents.
Read definitionChange order
A formal, signed modification to the construction contract that changes the scope of work, the contract price, the schedule, or any combination of the three.
Read definitionDesign basis (also: Basis of design)
The documented set of requirements, criteria, codes, site data and assumptions from which a design is developed — the premises of the project, written down.
Read definitionFront-end engineering design (FEED)
The engineering stage between concept and detailed design in which a project is defined thoroughly enough to fix its cost estimate, support the investment decision and form the basis of EPC tendering.
Read definitionIssued for Construction (IFC)
The revision status marking a document as reviewed, approved and released as the version from which construction may proceed.
Read definitionAs-built documentation
Project documentation revised at completion to record what was actually constructed, incorporating every field change, deviation and accepted concession made during the build.
Read definitionHandover package
The structured set of documentation transferred from the project to the owner at completion — as-builts, vendor documents, certificates, test records and operating information — constituting the asset's permanent record.
Read definitionProfessional engineer seal
The stamp of a licensed professional engineer applied to design documents in US and Canadian practice, signifying that the work was prepared by or under the direct supervision of that engineer, who accepts legal responsibility for it.
Read definitionSignature and seal requirements
The rules, differing by jurisdiction, that determine who must sign, approve or stamp design documents for those documents to be valid for permitting and construction.
Read definitionRevision control
The discipline of identifying, tracking and distributing document versions so that at any moment there is exactly one revision of each document that everyone agrees is current.
Read definitionDetailed design (detail engineering)
The engineering stage that converts a defined project into buildable documentation — the full set of drawings, models, isometrics, schedules and take-offs from which construction and procurement actually proceed.
Read definitionWorking documentation (the design/working split)
In CIS practice, the second of two documentation stages: the construction-level documents developed after the approved design documentation, which is the stage that undergoes state examination.
Read definitionInterdisciplinary check (IDC / squad check)
The formal circulation of one discipline's deliverables to all affected disciplines for review and comment before the documents are issued.
Read definitionMaster document register (MDR)
The controlled index of every document a project will produce — with numbers, titles, revisions, statuses and planned dates — serving as both the catalogue of the documentation and the instrument for measuring engineering progress.
Read definitionTransmittal
The formal cover record accompanying documents sent between project parties, establishing exactly which documents, at which revisions, were sent to whom, when and for what purpose.
Read definitionVendor documentation
The documents produced by equipment suppliers — drawings, datasheets, calculations, manuals and certificates — that must be reviewed by the project and integrated into its documentation set.
Read definitionDeviation request (concession)
A formal request, raised before the work is done, for permission to depart from a specified requirement — as distinct from a non-conformance report, which records a departure after the fact.
Read definitionHold
A marked restriction meaning "do not proceed past this point without resolution" — applied on drawings to areas pending information, and in inspection plans to work stages requiring sign-off before continuing.
Read definitionManagement of change (MOC)
A formal process for evaluating, approving and documenting changes to a design, process or facility after its basis has been established, ensuring each change is reviewed for its consequences before it is made.
Read definitionPunch list
The list of incomplete, defective or outstanding items identified as a project approaches completion, each to be corrected and signed off before the work is finally accepted.
Read definitionAuthority having jurisdiction (AHJ)
The organisation, office or official with the legal authority to enforce a code or regulation on a project and to approve or reject the work under it.
Read definitionCluster C: Standards and normative base
Standards and normative base
Standard
A document, established by consensus and approved by a recognised body, that sets out requirements, rules or characteristics for products, processes or services, intended for common and repeated use.
Read definitionCode
In construction usage, a body of minimum mandatory requirements for the design and construction of facilities, given legal force by the jurisdiction that adopts it.
Read definitionTechnical regulation
A government-issued document laying down mandatory requirements for products or their related processes, with which compliance is compulsory as a matter of law rather than choice.
Read definitionNormative base
The complete body of normative documents — codes, standards, technical regulations and norms — in force for a given jurisdiction, sector or project at a given point in time.
Read definitionSuperseded standard
A standard that has been replaced by a newer edition or a different document and is no longer the current version — though it may still legitimately govern existing designs, contracts and facilities.
Read definitionMandatory vs voluntary standard
The distinction between standards whose application is required by law and those applied by choice — with the caveat that a voluntary standard becomes binding the moment a regulation or contract cites it.
Read definitionHarmonised standard
In EU usage, a European standard developed at the European Commission's request and cited in the Official Journal, so that compliance with it grants presumption of conformity with EU legislation; more loosely, any standard aligned across jurisdictions.
Read definitionSpecification
A project document that defines the requirements for the materials, products, workmanship and performance of a particular scope of work — the written half of the design, alongside the drawings.
Read definitionDatasheet
A structured document recording the defining technical parameters of a specific equipment item or instrument — its duty, operating conditions, materials, dimensions and connections — maintained from requisition through vendor completion to as-built.
Read definitionEurocodes
The suite of ten European standards, EN 1990 to EN 1999, governing structural and geotechnical design, applied together with the national annex of the country where the structure will be built.
Read definitionInternational Building Code (IBC)
A model building code published by the International Code Council, adopted — usually with amendments — by jurisdictions across the United States and in several other countries as the legal basis of building regulation.
Read definitionISO
The International Organization for Standardization — a worldwide federation of national standards bodies that develops voluntary international standards across nearly every field of technology, industry and management.
Read definitionNational annex
A country-specific supplement to an international or European standard that fixes the parameters and choices the parent standard leaves open to national determination, making the standard usable in that jurisdiction.
Read definitionClause reference
A citation of a specific numbered provision within a standard or code — the level at which compliance is actually demonstrated, disputed and reviewed.
Read definitionSNIP
The construction norms and rules of the Soviet standardisation system — the ancestor of today's CIS construction codes, largely superseded, still widely cited by habit and searched by name.
Read definitionGOST
The standards of the Soviet and post-Soviet standardisation system — today, interstate standards maintained across the CIS, alongside national derivatives such as Russia's GOST R and Kazakhstan's ST RK.
Read definitionSN RK and SP RK
Kazakhstan's construction normative system: SN RK, the state building norms carrying mandatory requirements, and SP RK, the rules sets providing accepted methods of meeting them — with the Eurocodes admitted as an alternative design route.
Read definitionEAEU technical regulations
Mandatory technical requirements adopted at the level of the Eurasian Economic Union, applying directly and uniformly across its member states, with conformity confirmed by the EAC mark.
Read definitionASME
The American Society of Mechanical Engineers — publisher of the Boiler and Pressure Vessel Code and the B31 piping codes, the dominant standards for pressure equipment across much of the world.
Read definitionASTM
ASTM International — a standards body whose tens of thousands of material, product and test-method standards are the reference layer cited underneath specifications and codes worldwide.
Read definitionAPI
The American Petroleum Institute — whose standards for equipment, materials and practices are the de facto global technical language of the oil and gas industry, applied far beyond any American jurisdiction.
Read definitionIEC
The International Electrotechnical Commission — ISO's electrotechnical counterpart, whose standards govern electrical, electronic and instrumentation engineering worldwide, including equipment for explosive atmospheres and functional safety.
Read definitionNFPA
The National Fire Protection Association — publisher of the US fire-safety canon, including the National Electrical Code (NFPA 70) and the sprinkler, alarm and life-safety standards adopted throughout North American practice and exported with it.
Read definitionNormative reference
The mechanism by which one standard incorporates provisions of another by citing it — making the cited document's requirements part of the citing one, to the extent stated.
Read definitionStandards body
An organisation that develops and publishes standards through a consensus process — international, regional, national or industry-based, each with its own scope, membership and authority.
Read definitionEdition, amendment and corrigendum
The three instruments by which a published standard changes: a new edition replaces it, an amendment modifies parts of it, and a corrigendum corrects errors in it — with the current version being the sum of all three.
Read definitionPrescriptive vs performance-based codes
The two philosophies of regulation: prescriptive codes state exactly what to build, performance-based codes state what the result must achieve — and most real systems combine both.
Read definitionCluster D: Delivery and contracting
Delivery and contracting
EPC
A contracting model — Engineering, Procurement and Construction — in which a single contractor takes responsibility for designing, buying and building a complete facility under one contract, usually for a fixed price.
Read definitionEPCM
A delivery model — Engineering, Procurement and Construction Management — in which the contractor provides engineering and manages procurement and construction as a professional service, while the construction contracts and the risk remain with the owner.
Read definitionLump-sum contract
A contract in which the contractor agrees to deliver a defined scope of work for a fixed total price, carrying the risk that the work costs more than the price.
Read definitionCost-plus contract
A contract in which the owner reimburses the contractor's actual costs of performing the work, plus an agreed fee — fixed, percentage-based or incentive-linked.
Read definitionTender
The formal process by which an owner invites, receives and evaluates competing offers for a defined scope of work — and also the name of the offer itself.
Read definitionPrequalification
The screening of contractors or suppliers for capability before they are invited to bid — assessing financial standing, experience, resources and safety record so that the tender list contains only parties who could actually perform.
Read definitionContractor and subcontractor
The contractual chain of construction: the (main) contractor holds the contract with the owner, and subcontractors hold their contracts with the contractor — not with the owner.
Read definitionAsset owner
The party that owns, finances and will operate the facility being built — the entity for whose benefit the entire project structure exists, and whose decisions every other party is waiting on.
Read definitionDesign institute
An institutional form of design organisation — characteristic of the CIS, China and neighbouring systems — in which a licensed organisation, rather than an individually licensed engineer, produces design documentation and carries responsibility for it.
Read definitionGreenfield
A project built on a previously undeveloped site, with no existing facility to constrain the design — and no existing infrastructure to build upon.
Read definitionBrownfield
Work performed within or immediately alongside an existing facility, where the design must connect to, coexist with, and often keep running the plant that is already there.
Read definitionRevamp
The modification of an existing operating unit to change what it does — more capacity, different feedstock, better efficiency, new products — reusing as much of the existing plant as the new duty allows.
Read definitionTurnaround
A planned, scheduled shutdown of an operating unit for inspection, maintenance and modification work that cannot be done while it runs — executed at maximum intensity because every day of downtime is lost production.
Read definitionScope of work
The contractual description of everything a contractor is obliged to perform and deliver — and, by its boundaries, everything it is not.
Read definitionFIDIC
The International Federation of Consulting Engineers — publisher of the standard forms of contract that are the default framework for international construction and EPC projects across much of the world.
Read definitionLump-sum turnkey (LSTK)
EPC contracting in its most complete commercial form: a fixed price for a finished facility, handed over tested and ready to operate — the owner turns the key.
Read definitionITT, RFP and RFQ
The three standard solicitation instruments: an invitation to tender seeks priced bids on a defined scope, a request for proposals seeks solutions as well as prices, and a request for quotations seeks prices for specified supply — though RFQ also means "request for qualifications" in some markets.
Read definitionOwner's engineer
An engineering organisation retained by the owner to act as its technical representative — reviewing the contractor's design, monitoring execution, and supplying the engineering judgement the owner does not carry in-house.
Read definitionProject management consultant (PMC)
An organisation engaged to manage a project on the owner's behalf — running schedule, cost, contracts and interfaces across all the other parties — as the owner's agent rather than as a contractor for the work itself.
Read definitionLong-lead items
Equipment and materials whose procurement time — engineering, fabrication and delivery — is so long that they must be ordered early, often before the main contract or even the investment decision, to protect the project schedule.
Read definitionVariation
In FIDIC and UK-influenced contracts, an instructed change to the works — the sibling of the change order, with its own mechanics: the instruction comes first, and the valuation follows.
Read definitionLiquidated damages
Pre-agreed sums, fixed in the contract, payable for defined failures — most commonly per day of delay past the completion date, and in EPC contracts also per unit of performance shortfall.
Read definitionRetention
A percentage withheld from each progress payment — commonly five to ten percent — held by the paying party as security for completion and the correction of defects, and released in stages after the work is done.
Read definitionFree-issue materials
Materials or equipment that the owner procures and supplies to the contractor for incorporation into the works — moving the supply obligation, and its risks, from contractor to owner.
Read definitionBid levelling
The adjustment of received bids onto a common basis — aligning scope interpretations, exclusions, clarifications and commercial terms — so that the comparison is between equivalent offers rather than raw totals.
Read definitionLocal content
Requirements — statutory or contractual — that a defined share of a project's labour, goods and services be sourced from the host country, common across resource-rich jurisdictions.
Read definitionCluster E: Drawings and engineering data
Drawings and engineering data
P&ID
A Piping and Instrumentation Diagram — the schematic drawing showing every pipe, valve, item of equipment, instrument and control function of a process system, and how they connect.
Read definitionPFD
A Process Flow Diagram — the higher-level schematic showing a facility's major equipment and main process streams, with the key operating conditions and the heat and material balance data.
Read definitionPiping isometric
A drawing of a single pipeline, or part of one, drawn in isometric projection without scale — carrying the dimensions, welds, materials and bill of materials from which the line is fabricated and erected.
Read definitionLine list
The register of every piping line in a facility, recording each line's number, size, piping class, origin and destination, operating and design conditions, and requirements for insulation and testing.
Read definitionEquipment list
The register of all tagged equipment on a project, recording each item's tag number, description, service and key parameters — the index against which equipment is engineered, purchased and tracked.
Read definitionTag number
The unique identifier assigned to each engineered item in a facility under the project's tagging convention — the key by which the same physical object is recognised across every drawing, list, system and decade.
Read definitionOff-page connector
A symbol marking where a line on a schematic continues on another sheet, carrying the reference to the drawing and connector where it resumes.
Read definitionRedline
A marked-up copy of a drawing recording changes made or required — traditionally in red pen — serving as the field's running record of how the work departed from the issued design.
Read definitionRevision cloud
The cloud-shaped outline drawn around the changed areas of a drawing, paired with a revision tag, so that a reader can see at a glance what differs from the previous issue.
Read definitionGeneral arrangement drawing
A scaled drawing showing the physical arrangement of equipment, structures and major components within an area — in plan, elevation and section — defining where everything actually sits.
Read definitionPlot plan
The scaled layout of an entire facility — units, buildings, roads, pipe racks and infrastructure — fixing the spatial relationships and spacing on which safety, cost and future expansion all depend.
Read definitionSingle-line diagram
The electrical schematic that represents a facility's power system with each circuit drawn as a single line — showing sources, transformers, switchgear, distribution and protection in one connected view.
Read definitionBIM
Building Information Modelling — the practice of designing and delivering construction projects through structured, object-based digital models that carry data as well as geometry, shared between the parties.
Read definitionLevel of development (LOD)
A framework specifying how developed and reliable a model element is at a given stage — commonly on a scale from LOD 100 (conceptual) to LOD 500 (field-verified as-built) — and therefore what its geometry and data may be relied on for.
Read definitionClash detection
The automated checking of a combined multi-discipline 3D model for spatial conflicts — elements occupying the same space, or violating required clearances — before those conflicts are found by construction.
Read definitionIndustry Foundation Classes (IFC)
The open, vendor-neutral data schema for describing and exchanging building information models — the common language by which BIM data moves between different software tools.
Read definitionDEXPI
The process industry's standard for exchanging intelligent P&ID data — letting the full content of a P&ID, its objects, topology and attributes, move between software systems in machine-readable form.
Read definitionDigital twin
A digital representation of a physical asset that is kept connected to it — updated with the asset's data so that the model reflects, and can be used to reason about, the asset's actual state.
Read definitionKnowledge graph
A way of structuring information as a network of entities and typed relationships — things, connected by what they mean to each other — that systems can traverse and query.
Read definitionCAD
Computer-aided design — the family of software tools in which drawings and models are authored, from 2D drafting through 3D modelling to data-centric design systems.
Read definition2D drafting and 3D modelling
The two modes of producing engineering documentation — authoring scaled drawings directly, versus building a 3D model from which drawings and data are derived — and the hybrid reality in which most projects run both.
Read definitionSmart P&ID (intelligent P&ID)
A P&ID authored as structured data — every symbol an object with attributes, every line a connection in a topology — so that the drawing is a view of a database rather than a picture of a plant.
Read definitionBill of materials (BOM)
The list of materials and components required to build a defined assembly or drawing — such as the table on a piping isometric — as distinct from a material take-off, which aggregates across a project, and a bill of quantities, which measures work for pricing.
Read definitionLegend sheet
The sheet at the front of a drawing set that defines the symbols, line types, abbreviations and identification conventions used throughout it — the key without which the set cannot be reliably read.
Read definitionPiping class (pipe spec)
A specification defining the approved materials and components — pipe, fittings, flanges, valves, gaskets, bolting — for a given service, identified by a class code carried on the P&IDs and line list.
Read definitionTie-in
A defined point at which new work connects to an existing system — specified, numbered and managed as a register, because each one is a controlled intrusion into a live facility.
Read definitionPoint cloud / laser scanning
The capture of existing physical conditions as millions of measured 3D points — producing a geometric record of a facility as it actually stands, against which brownfield design can be checked.
Read definitionData handover
The transfer of structured engineering information — tag registers, attributes, relationships, documents linked to the assets they describe — from project to owner, as distinct from handing over the documents alone.
Read definitionISO 15926
The international standard for representing and integrating lifecycle information about process plants — a common data model and reference vocabulary intended to let plant information move between systems, organisations and decades without losing its meaning.
Read definitionSupplemental glossary
Process safety and connectivity
Hazard and Operability Study
The structured PHA methodology that uses guide words to systematically identify hazards at every node of a process. The dominant PHA method for complex continuous processes.
Read definitionLeak Detection and Repair
The EPA regulatory program under which facilities handling VOC and HAP streams systematically monitor equipment for fugitive emissions and repair detected leaks within specified timeframes.
Read definitionProcess Hazard Analysis
The systematic evaluation of hazards OSHA PSM requires under 29 CFR 1910.119(e). Must be revalidated at least every five years; HAZOP is the most common methodology.
Read definitionProcess Safety Information
The documentation package OSHA PSM requires on every covered process — the factual foundation on which PHA, MOC, Mechanical Integrity, and Pre-Startup Safety Review all depend.
Read definitionFrom-To List
The tabular record of where every piping line begins and ends — the connectivity backbone that ties P&IDs, isometrics, and line lists into a single engineering knowledge graph.
Read definitionPut this vocabulary to work.
See how Armeta understands the standards, catalogs, drawings, specifications, and project records behind these terms.