What Changed in the Codes You Design To
Every code and standard on this site is reviewed against a specific edition. This hub is where we make that review visible — what edition we track, when we last checked it, what changed from the previous edition, and exactly what that means for your drawings, calculations, and specifications.
The codes and standards we track, the edition each page covers, and what changed.
How to use this page: each standard below links to a dedicated page with the edition we currently track, a summary of what changed versus the previous edition (in our own words — never reproduced from the standard itself), common jurisdiction adoption caveats, and a practical checklist of what to revisit in existing work. These are educational summaries, not a substitute for the official published standard or your local building department's amendments.
What changed for electricians, engineers, and inspectors — article-by-article, in plain language.
Fire-alarm design implications of the latest edition — initiating devices, notification, and signaling changes.
What changed for commercial HVAC design — envelope, equipment efficiency, and controls requirements.
Wind, seismic, snow, and load combination changes — what shifts in your structural design basis.
Updates for OT and industrial-control security — what changed for SCADA, PLC, and ICS network design.
Codes and standards are revised on a cycle, and a design that was compliant under one edition can be non-compliant — or simply out of date — under the next. Every calculator, article, and design tool on this site is written against a specific edition, and that edition eventually changes. Rather than leaving that invisible, this page tracks it directly: what we currently reference, when we last reviewed it against the newest publication, and — critically — what practically changes for someone doing real design work. Jurisdictions adopt code editions on their own timelines and often layer local amendments on top, so always confirm the edition and any local amendments in effect with your local authority having jurisdiction (AHJ) before relying on any specific value for a real project.
A code is a body of requirements meant to be adopted, as a whole, into law by a governing jurisdiction — a state, county, or city. Once adopted, it becomes legally enforceable, typically through a building permit and inspection process. The National Electrical Code (NFPA 70), the International Building Code, and the International Fire Code are all model codes: written by an organization, but with no legal force anywhere until a specific jurisdiction formally adopts a specific edition, often layering its own local amendments on top.
A standard is a documented, agreed-upon technical requirement, test method, or performance specification for a narrower scope — a material property, a design calculation method, a piece of equipment, or a work practice. A standard becomes enforceable only when something else — a code, a specification, a contract, or an insurer’s requirement — references or incorporates it. ASME BPVC, ASTM A992, and IEEE 1584 are all standards: technically authoritative on their own subject, but not law until something legally binding points to them.
A city adopts the International Building Code (a code) as its legal building code. The IBC, in turn, requires that structural concrete be designed per ACI 318 (a standard) and that structural steel meet ASTM A992 (another standard). Neither ACI 318 nor ASTM A992 was independently voted into law by the city — they became enforceable on that project the moment the IBC, which the city did adopt, pointed to them. This reference chain — a code pulling in dozens of standards by citation — is how almost every real construction project ends up legally bound by standards that were never separately adopted as law in their own right.
Codes exist primarily to protect public health, safety, and welfare — minimum requirements a jurisdiction has decided are non-negotiable for anyone building or operating within its authority.
Standards exist primarily so that engineers, manufacturers, and contractors working independently of each other produce compatible, predictable, comparable results — the same test method, the same material grade, the same design method.
A code is enforced by an Authority Having Jurisdiction (AHJ) — a building department, fire marshal, or similar official — through plan review, permitting, and inspection.
A standard is typically enforced by whoever specified it: an engineer's stamped drawing, a purchasing specification, an insurer's policy condition, or a code that cites it by reference.
When you hit a requirement in a project, it’s worth asking which kind of document it came from, because the answer changes what you do next. If it’s from an adopted code, the question is which edition and which local amendments your specific AHJ is enforcing — that is a jurisdiction question, not an engineering-judgment question, and the only reliable source is the AHJ itself. If it’s from a standard, the question is whether anything actually requires it on this project — a referencing code, a client specification, a professional obligation, or an insurer’s condition — and, if so, which edition that reference points to, since a standard can be revised on its own schedule independent of whatever code or contract cites it. Treating every requirement as if it were the same kind of document is how projects end up citing a standard’s superseded edition, or assuming a voluntary industry standard has the force of law when nothing on that specific project actually made it mandatory.
Behind every code and standard is an organization that develops, maintains, and periodically revises it. This directory maps the standards-issuing bodies most relevant to each major engineering discipline, so you know where a given requirement actually originates and where to go for the authoritative source.
Important: the summaries below describe each organization's general scope and role in our own words — they are not excerpts or reproductions of any published standard, and organizations frequently update their scope, structure, and publications. Always consult the official standard or code, published directly by the issuing organization, before relying on it for a real design, submittal, or compliance decision, and confirm which edition your local authority having jurisdiction (AHJ) has adopted.
Mobile telecommunications standards, including LTE and 5G.
Used for: The complete technical specification set defining how 4G LTE and 5G cellular networks operate — air interface, core network architecture, and device requirements.
How it’s used: Telecommunications and RF engineers designing cellular infrastructure, DAS (distributed antenna systems), or private 5G networks work from 3GPP release specifications to ensure equipment interoperability.
Used for: The overall architecture of 5G core networks.
How it’s used: Network engineers use it to understand 5G core functions.
Used for: Security requirements and procedures for 5G.
How it’s used: Security engineers use it to assess 5G security.
Used for: An overview of the 5G New Radio access technology.
How it’s used: Radio engineers use it as an entry point to NR.
Used for: Radio performance requirements for 5G devices, including frequency bands.
How it’s used: Device and test engineers use it for band and RF requirements.
Used for: An overview of the LTE radio access network.
How it’s used: Radio engineers use it as an entry point to LTE.
Used for: The requirements on 5G services, such as latency and reliability targets.
How it’s used: Planners use it to compare 5G capabilities with application needs.
Used for: The architecture of the LTE core network.
How it’s used: Core network engineers use it for LTE design.
Highway and transportation infrastructure design standards.
Used for: The controlling design standard for highway bridges in the U.S. — load factors, live-load models (design truck/lane), and material-specific design provisions.
How it’s used: Bridge engineers design girders, decks, and substructures to its load-and-resistance-factor provisions; state DOTs require conformance for any bridge in the public highway system.
Used for: Geometric design criteria for roadways — lane widths, sight distance, horizontal/vertical curve design, and design speed relationships.
How it’s used: Civil and transportation engineers set roadway alignment, curve radii, and sight-distance requirements from its tables during roadway design.
Used for: Guidance on clear zones, barriers and roadside hazards.
How it’s used: Highway designers lay out clear zones and barriers with it.
Used for: Methods for inspecting and rating existing bridges.
How it’s used: Bridge owners use it to rate load capacity.
Used for: Construction requirements that go with the LRFD design specifications.
How it’s used: Contracts cite it for materials and workmanship on bridges.
Used for: A method for designing pavement structures using materials, traffic and climate.
How it’s used: Pavement engineers use it for design and analysis.
Used for: The standard laboratory compaction test for soil.
How it’s used: Highway agencies specify field compaction targets from it.
Used for: A soil classification system used for highways.
How it’s used: Geotechnical and highway engineers classify subgrade soils with it.
Concrete design, materials, and construction practice standards.
Used for: The controlling design standard for reinforced concrete structures — flexural and shear design, reinforcement detailing, and development lengths.
How it’s used: Structural engineers design concrete beams, slabs, columns, and foundations to its strength-design provisions; the IBC directly references it by adoption.
Used for: A reference specification for concrete materials, mixing, placing, and finishing that can be incorporated by reference into project specs.
How it’s used: Structural engineers cite ACI 301 in project specifications rather than writing bespoke concrete-placement requirements for every project.
Used for: Design requirements for liquid-containing concrete structures such as water and wastewater tanks.
How it’s used: Water and wastewater engineers use it for tanks and channels.
Used for: A simplified code for concrete in one- and two-family dwellings and townhouses.
How it’s used: Residential designers and builders use it for footings and walls.
Used for: Acceptable tolerances for concrete elements and surfaces.
How it’s used: Specifiers cite it in project documents for dimensional tolerances.
Used for: A method for proportioning concrete mixes.
How it’s used: Mix designers and testing labs start from it.
Used for: Requirements for assessing and repairing existing concrete structures.
How it’s used: Repair engineers use it for evaluation and repair design.
Performance and certification standards for HVACR equipment.
Used for: The standardized test procedure behind published SEER/SEER2, EER, and HSPF ratings for residential and light-commercial AC and heat pump equipment.
How it’s used: HVAC engineers select equipment by comparing AHRI-certified performance ratings across manufacturers, and code-mandated minimum efficiency requirements are stated in these same AHRI rating terms.
Used for: Standardized test conditions and rating procedure for water-cooled and air-cooled chillers.
How it’s used: Mechanical engineers compare chiller selections using AHRI-rated kW/ton efficiency values at standard conditions, ensuring an apples-to-apples comparison across vendors.
Used for: The rating procedure for rooftop units and other larger unitary equipment.
How it’s used: Engineers compare capacity and efficiency ratings that follow it.
Used for: Rating procedure for VRF systems.
How it’s used: Designers compare VRF systems with the published ratings.
Used for: Rating of cooling and heating coils.
How it’s used: Engineers select coils using certified data.
Used for: Rating of the supply fans in central station air handlers.
How it’s used: Engineers use certified fan data when sizing air handlers.
Used for: Purity and quality specifications for refrigerants.
How it’s used: Contractors and buyers check refrigerant quality against it.
Chemical process safety and engineering practice guidance (e.g., CCPS).
Used for: Widely used process-safety-engineering guidance documents — inherently safer design, layer of protection analysis (LOPA), and process hazard analysis (PHA) methodology.
How it’s used: Process safety engineers structure PHA/HAZOP studies and LOPA safety-integrity determinations following CCPS methodology, which regulators (OSHA PSM, EPA RMP) recognize as good engineering practice.
Used for: A semi-quantitative method for judging whether safeguards reduce a hazard scenario enough.
How it’s used: Process safety teams use it after a HAZOP to size protection layers.
Used for: Methods such as HAZOP and what-if analysis for finding process hazards.
How it’s used: Teams use it to plan and run hazard studies.
Used for: A management-system framework for process safety.
How it’s used: Organizations use it to build or assess process safety programs.
Used for: Quantitative methods for estimating process risk.
How it’s used: Risk analysts use it for consequence and frequency studies.
Structural steel design, fabrication, and erection standards.
Used for: The controlling design specification for structural steel members and connections — allowable stress and LRFD design methods.
How it’s used: Structural engineers size steel beams, columns, and connections to its provisions, typically through the companion Steel Construction Manual's design tables.
Used for: Additional detailing and design requirements for steel structures in seismic design categories requiring ductile behavior.
How it’s used: Structural engineers on projects in higher seismic design categories apply its special moment-frame or braced-frame detailing requirements on top of the base AISC 360 design.
Used for: Section properties, design tables and the code references used for everyday steel design.
How it’s used: Structural engineers use its tables to select members and connections.
Used for: The agreed responsibilities and practices between owners, designers, fabricators and erectors.
How it’s used: Contracts and shop drawing reviews refer to it.
Used for: Moment connection details that have been tested and approved for seismic use.
How it’s used: Engineers detail seismic moment connections from it.
Coordinates and accredits U.S. voluntary consensus standards across industries.
Used for: A jointly ANSI/TIA-published standard for structured cabling in commercial buildings — cable categories, topology, and performance requirements.
How it’s used: Telecommunications designers specify Category 6/6A cabling and horizontal/backbone topology against it when designing a building's structured cabling infrastructure.
Used for: Performance and marking requirements for safety eyewear and face protection used in industrial and construction settings.
How it’s used: Safety and industrial engineers specify Z87.1-marked eyewear in PPE programs, and it's the reference OSHA points to for eye-protection compliance.
Used for: Safety requirements for specific classes of machine tools — guarding, control reliability, and risk assessment for equipment like presses, machining centers, and robots.
How it’s used: Manufacturing and industrial automation engineers perform a risk assessment against the relevant B11 standard for a given machine type to determine required guarding and safety-control-system category.
Used for: Safety rules for the installation, operation, and maintenance of electric supply and communication lines — the code utilities use for overhead and underground power lines, distinct from the NEC's premises-wiring scope.
How it’s used: Utility and power-distribution engineers design pole lines, clearances, and grounding for utility infrastructure to the NESC rather than the NEC, which stops at the utility service point.
Used for: Consistent safety signs, colors and formats for hazard communication, including signal words such as Danger and Warning.
How it’s used: Facility and safety engineers design equipment labels and area signs to it.
Used for: Standard nominal system voltages and the service and utilization voltage ranges for U.S. power systems.
How it’s used: Engineers check that equipment ratings and voltage drop stay within its ranges.
Used for: Requirements for fall protection and fall arrest systems, equipment and training.
How it’s used: Safety managers and designers specify anchors, harnesses and lifelines to it.
Used for: Pipe marker colors and labeling for identifying contents and flow direction.
How it’s used: Plant and building engineers specify pipe labeling to it.
Used for: Technical requirements that make buildings and facilities accessible to people with disabilities; the model code cites this ANSI-approved standard.
How it’s used: Architects and engineers use it for dimensions, clearances and fixtures in accessible spaces.
Oil and gas equipment, process safety, and pipeline standards.
Used for: Design, fabrication, and inspection requirements for large, field-erected, welded steel storage tanks.
How it’s used: Process and mechanical engineers design tank shell thickness, foundation loading, and appurtenances to it for atmospheric and low-pressure storage tanks at refineries, terminals, and bulk plants.
Used for: In-service inspection intervals and repair/alteration criteria for API 650 tanks over their operating life.
How it’s used: Mechanical integrity engineers schedule tank inspections and evaluate corrosion/repair findings against its acceptance criteria to determine continued fitness for service.
Used for: In-service inspection, repair, and rerating requirements for process piping systems.
How it’s used: Mechanical integrity engineers at refineries and chemical plants use it to set piping inspection intervals and corrosion-rate-based remaining-life calculations.
Used for: Design and performance requirements for centrifugal pumps used in petroleum and petrochemical service, beyond typical commercial pump standards.
How it’s used: Process/mechanical engineers write pump procurement specs referencing API 610 for critical hydrocarbon service pumps where a standard commercial pump spec would be insufficient.
Used for: Requirements for steel line pipe used in pipelines.
How it’s used: Pipeline engineers specify grade, wall thickness and testing from it.
Used for: Requirements for valves used in pipelines.
How it’s used: Designers and buyers specify gate, ball and check valves to it.
Used for: Inspection, repair and rating requirements for in-service pressure vessels.
How it’s used: Inspectors and owners schedule inspections and rate vessels with it.
Used for: Sizing, selection and installation of pressure relief devices and relief systems.
How it’s used: Process engineers size relief valves and flare systems.
Used for: Methods to assess whether damaged equipment can stay in service.
How it’s used: Integrity engineers evaluate corrosion, cracks and dents.
Used for: A framework for planning inspections by risk.
How it’s used: Asset owners prioritize inspections with it.
Used for: Welding procedure, welder qualification and inspection requirements for pipelines.
How it’s used: Pipeline contractors qualify welders and procedures to it.
Used for: Requirements for compressors in refineries and process plants.
How it’s used: Buyers and engineers use it to specify compressors.
Structural and civil design load standards, including ASCE 7.
Used for: The controlling standard for structural design loads — dead, live, wind, snow, seismic, and flood loads, and how to combine them.
How it’s used: Structural engineers pull site-specific wind speed, seismic parameters, and snow load from its maps/tables as the starting input for every structural calculation on a project.
Used for: Design requirements for buildings in flood hazard areas — elevation requirements, flood-resistant materials, and foundation design in flood zones.
How it’s used: Structural and civil engineers on coastal or floodplain sites use it to set minimum finished-floor elevation and select flood-resistant construction methods below the design flood elevation.
Used for: Performance-based methodology for evaluating and retrofitting existing buildings for seismic performance.
How it’s used: Structural engineers evaluating an older building for a seismic retrofit or change of use follow its nonlinear analysis and performance-level procedures rather than designing it as new construction.
Used for: Loads to consider on a partly built structure and its temporary works.
How it’s used: Engineers check construction-stage loads with it.
Used for: Design requirements for steel lattice transmission towers.
How it’s used: Transmission line engineers use it for tower design.
Used for: Wind, ice and other loads on transmission lines and their structures.
How it’s used: Utility engineers determine line loading with it.
Used for: Procedures for wind tunnel testing used to find wind loads on structures.
How it’s used: Wind engineers specify and review wind tunnel studies against it.
HVAC, refrigeration, and building energy performance standards.
Used for: Minimum energy-efficiency requirements for commercial buildings — envelope performance, HVAC equipment efficiency, and lighting power density.
How it’s used: Mechanical and energy-modeling engineers demonstrate a building design meets or beats its baseline through prescriptive compliance or whole-building energy modeling, often required for a building permit or LEED credit.
Used for: Minimum outdoor-air ventilation rates for commercial and institutional buildings, by occupancy and space type.
How it’s used: HVAC engineers size outdoor-air intake and calculate ventilation rates per its occupancy-based tables during load calculations, feeding directly into air handler sizing.
Used for: Safety requirements for refrigeration systems by refrigerant classification — machine room ventilation, refrigerant quantity limits, and detection/alarm requirements.
How it’s used: Mechanical engineers designing refrigeration or large chiller plants size machine-room ventilation and specify refrigerant monitoring/alarm systems to its requirements based on the refrigerant's safety group.
Used for: Defines the combinations of temperature, humidity, and air speed that constitute an acceptable indoor thermal comfort range.
How it’s used: HVAC engineers use its comfort-zone charts to set design setpoints and to document that a space design falls within an acceptable comfort range, sometimes for LEED comfort credits.
Used for: Ventilation, pressure-relationship, and air-change-rate requirements specific to hospitals and outpatient facilities, by room type (OR, isolation room, etc.).
How it’s used: Healthcare HVAC engineers set air-change rates and pressure relationships (positive/negative) per its room-by-room table, which most healthcare facility codes explicitly reference as mandatory.
Used for: The refrigerant numbering and the toxicity and flammability safety classes such as A1, A2L and B1.
How it’s used: Engineers use the classes when applying ASHRAE 15 and local codes.
Used for: The test that produces the MERV rating of air filters.
How it’s used: Engineers specify filters by MERV rating.
Used for: Energy efficiency requirements for data centers, including mechanical and electrical system efficiency.
How it’s used: Data center designers use it where adopted in place of or beside 90.1.
Used for: The BACnet protocol used by building automation systems.
How it’s used: Controls engineers specify BACnet devices and points for interoperability.
Used for: Requirements for sustainability, energy, water and indoor air quality in high-performance buildings.
How it’s used: Designers use it for green building projects and adopted jurisdictions.
Used for: Standard control sequences for common HVAC systems.
How it’s used: Controls engineers write sequences from it.
Used for: Requirements for reducing the risk of airborne infection through ventilation and air cleaning.
How it’s used: Engineers use it to set infection-risk-management strategies in buildings.
Mechanical engineering, pressure vessel, piping, and equipment standards.
Used for: The controlling design, fabrication, and inspection standard for boilers and pressure vessels in the U.S. — covers material selection, wall-thickness calculations, welding qualification, and inspection.
How it’s used: Pressure vessel and process engineers design vessel wall thickness and nozzle reinforcement to its formulas, and fabricators must hold an ASME "U" stamp certification to legally build code vessels.
Used for: Design, materials, and fabrication requirements for piping systems — B31.1 for power/utility piping, B31.3 for process piping in chemical and industrial plants.
How it’s used: Piping engineers calculate wall thickness, flexibility (thermal expansion), and support spacing to the applicable B31 code section for the specific service (steam, process fluid, etc.).
Used for: The geometric dimensioning and tolerancing system used on mechanical engineering drawings to specify allowable variation in part form, size, and location.
How it’s used: Mechanical designers apply GD&T symbols and tolerance zones to a drawing so manufacturing and quality inspection have an unambiguous, measurable definition of an acceptable part.
Used for: Design and safety requirements for elevators, escalators, and moving walks — car safety devices, hoistway construction, and emergency operation.
How it’s used: Elevator consultants and building engineers design hoistway dimensions, machine room requirements, and life-safety interfaces (fire alarm recall) to it, and it's enforced by elevator inspectors.
Used for: Dimensions, pressure-temperature ratings and materials for pipe flanges and fittings.
How it’s used: Piping designers select flange class and facing from it.
Used for: Design, construction and operation requirements for gas pipelines.
How it’s used: Pipeline engineers use it for wall thickness, testing and integrity management.
Used for: Safety requirements for cranes, hoists, slings and rigging equipment.
How it’s used: Safety managers and riggers use the relevant part for inspection, operation and maintenance.
Used for: Thread forms, sizes and tolerances for inch-series fasteners.
How it’s used: Mechanical designers call out thread series and classes from it.
Used for: Dimensions and quality of bolts, nuts, screws and washers.
How it’s used: Designers and buyers specify standard fasteners from it.
Used for: Procedures for testing the performance of power and process equipment such as boilers, turbines and pumps.
How it’s used: Plants run acceptance tests under the relevant code to verify guaranteed performance.
Product performance standards for plumbing safety devices (backflow preventers, etc.).
Used for: Performance and testing requirements for reduced-pressure-principle backflow preventers, used to protect potable water from contamination.
How it’s used: Plumbing engineers specify ASSE 1013-listed backflow preventers on domestic water service entrances and irrigation connections per local health-department requirements.
Used for: Performance requirements for thermostatic mixing valves that limit hot water temperature at fixtures to prevent scalding.
How it’s used: Plumbing engineers specify ASSE 1070-listed mixing valves at lavatories and showers in codes/occupancies (schools, healthcare) requiring scald protection.
Used for: Performance requirements for atmospheric vacuum breakers.
How it’s used: Designers select backflow devices by application and type.
Used for: Requirements for devices that protect hose connections against backflow.
How it’s used: Plumbers install them on hose bibbs.
Used for: Requirements for double check assemblies.
How it’s used: Designers select them for low-hazard backflow protection.
Used for: Requirements for pressure-balancing and thermostatic shower valves.
How it’s used: Designers specify them to limit scalding.
Used for: Requirements for frost-resistant wall hydrants.
How it’s used: Used for exterior hose connections in cold climates.
Used for: Requirements for pressure vacuum breakers.
How it’s used: Used for backflow protection, such as on irrigation systems.
Used for: Requirements for fire protection backflow assemblies.
How it’s used: Fire protection designers specify them on sprinkler service lines.
Material property, test method, and product specification standards across nearly every discipline.
Used for: Chemical composition and mechanical property requirements for structural steel shapes and plate (A992 for wide-flange shapes, A36 for plate and general structural steel).
How it’s used: Structural engineers call out the specific ASTM steel grade on drawings, since a member's yield strength (used throughout the AISC design calculations) is defined by which ASTM spec it's ordered to.
Used for: The standardized furnace test that produces a building assembly's fire-resistance rating (1-hour, 2-hour wall/floor assemblies, etc.).
How it’s used: Architects and fire protection engineers select wall, floor, and door assemblies with an ASTM E119-tested (or UL-tested to the same method) fire rating that satisfies the IBC's required fire-resistance rating for that condition.
Used for: Material and dimensional specifications for PVC piping used in plumbing, irrigation, and drainage.
How it’s used: Plumbing and civil engineers specify PVC pipe by ASTM schedule/class designation to ensure pressure rating and dimensional compatibility with fittings.
Used for: Material-quality requirements for aggregate (C33) and Portland cement (C150) used in structural concrete mix designs.
How it’s used: Structural and materials engineers reference these when approving a concrete mix design submittal, ensuring the raw materials meet the quality basis ACI 318's strength design assumed.
Used for: Grades and properties of reinforcing bar.
How it’s used: Structural engineers specify rebar grade, such as Grade 60, from it.
Used for: The test method for the compressive strength of concrete cylinders.
How it’s used: Testing labs break cylinders to verify the specified concrete strength.
Used for: Specification for common steel pipe.
How it’s used: Piping designers specify steel pipe for water, steam and structural uses.
Used for: Requirements for high-strength structural bolts; it replaced the older A325 and A490 standards.
How it’s used: Steel designers specify structural bolts from it.
Used for: The method used to measure yield strength, tensile strength and elongation.
How it’s used: Materials labs test specimens to it.
Used for: Specification for copper tube types K, L and M.
How it’s used: Plumbing designers specify the tube type for water service and building supply.
Used for: The test that gives flame spread and smoke developed indexes.
How it’s used: Designers check interior finish and insulation against code limits on these indexes.
Used for: Modified and standard Proctor tests for soil compaction.
How it’s used: Geotechnical engineers set field compaction requirements from the maximum dry density.
Welding procedure, qualification, and inspection standards.
Used for: Welding procedure qualification, welder qualification, and inspection acceptance criteria for structural steel welding.
How it’s used: Structural and fabrication engineers require welders to hold AWS D1.1 qualification and inspectors to use its acceptance criteria (visual, and referenced NDT methods) for structural steel welds.
Used for: Welding requirements specific to highway bridge structures, typically more stringent than D1.1 for fatigue-critical members.
How it’s used: Bridge and transportation structural engineers specify D1.5 rather than D1.1 for bridge welds subject to cyclic loading and fatigue considerations.
Used for: How to qualify welding procedures and welders.
How it’s used: Fabricators prepare and qualify procedures with it.
Used for: The symbols used on drawings to describe welds.
How it’s used: Designers and welders read and draw weld symbols with it.
Used for: Welding requirements for structural aluminum.
How it’s used: Aluminum fabricators use it for qualification and inspection.
Used for: Welding requirements for structural stainless steel.
How it’s used: Stainless fabricators use it for qualification and inspection.
Used for: Additional welding requirements for seismic force-resisting systems.
How it’s used: Used together with D1.1 on seismic projects.
Used for: Welding requirements for aerospace hardware.
How it’s used: Aerospace fabricators qualify procedures to it.
Used for: The classification and requirements for common stick electrodes such as E7018.
How it’s used: Welders and buyers specify electrodes by its classifications.
Drinking water treatment, storage, and distribution standards.
Used for: Procedures for disinfecting new and repaired water mains before they're placed into service.
How it’s used: Civil/utility engineers and contractors follow its chlorination and bacteriological-testing procedure before a new water main is connected to an active distribution system.
Used for: Material, dimensional, and pressure-rating specifications for PVC pipe used in municipal water distribution.
How it’s used: Civil engineers specify AWWA C900/C905 class ratings for buried water main pipe sizing on utility drawings, distinct from the ASTM specs used for plumbing-scale PVC.
Used for: Requirements for ductile-iron pipe used in water mains.
How it’s used: Water designers specify pipe class and lining from it.
Used for: Requirements for gate valves used in water systems.
How it’s used: Water utilities specify gate valves to it.
Used for: Requirements for dry-barrel fire hydrants.
How it’s used: Utilities specify hydrants to it.
Used for: Requirements for butterfly valves in water service.
How it’s used: Designers specify large-diameter valves to it.
Used for: Requirements for large steel water pipe.
How it’s used: Designers specify steel pipe for transmission mains.
Used for: Design and construction requirements for welded steel water tanks.
How it’s used: Tank designers and utilities use it for elevated and ground tanks.
ICT and structured cabling design and installation best practices.
Used for: A comprehensive best-practices reference for designing and installing telecommunications and structured cabling infrastructure across an entire facility.
How it’s used: RCDD-credentialed (Registered Communications Distribution Designer) engineers use it as their primary design reference when scoping and specifying a building's complete ICT infrastructure.
Used for: Guidance on designing data centers, including space, power, cooling and cabling.
How it’s used: Data center designers use it with TIA-942.
Used for: Guidance for access control, video surveillance, intrusion and related security systems.
How it’s used: Security integrators use it for cabling and design of security systems.
Used for: Guidance on in-building wireless distribution.
How it’s used: RF designers use it for DAS planning.
Used for: Guidance on cabling for intelligent building systems.
How it’s used: Designers use it to plan building systems on a converged network.
Used for: Design practices for outside plant, including conduit, aerial and underground cable.
How it’s used: Outside plant designers use it as a reference.
Used for: Practical methods for installing cabling and related systems.
How it’s used: Installers use it for installation techniques.
Property-loss-prevention testing and certification, notably for fire protection equipment.
Used for: Loss-prevention engineering guidance covering fire protection, natural hazards, and equipment protection — often more stringent than minimum code.
How it’s used: Fire protection engineers on FM-insured facilities design sprinkler density and storage-commodity classification to FM Data Sheet requirements, which can exceed NFPA 13 minimums as an insurer condition.
Used for: Third-party testing and listing of fire protection and building products (similar in concept to a UL listing, run by a different certifying body).
How it’s used: Specifying engineers on FM-insured projects require "FM Approved" (not just UL Listed) products for certain fire protection equipment, since FM Global's own insurance underwriting requires it.
Used for: Sprinkler design, spacing and installation guidance used by FM insured properties.
How it’s used: Fire protection engineers design sprinkler layouts to it for FM properties.
Used for: Fire protection guidance for warehouse storage, including arrangement and sprinkler design.
How it’s used: Warehouse and distribution designers use it for storage protection.
Used for: Loss prevention guidance for data centers, covering power, cooling and fire protection.
How it’s used: Data center designers use it for construction, fire and electrical protection.
Used for: Guidance on designing roofs and building envelopes to resist wind.
How it’s used: Roof and envelope designers use it for wind uplift ratings.
Publishes the Uniform Plumbing Code and related mechanical standards.
Used for: A model plumbing code — an alternative to the ICC's International Plumbing Code, adopted in different jurisdictions (notably much of the western U.S.).
How it’s used: Plumbing engineers need to know which of the two model codes (UPC or IPC) their jurisdiction has adopted, since fixture-unit tables and venting requirements differ between them.
Used for: A model mechanical code, IAPMO's counterpart to the ICC's International Mechanical Code.
How it’s used: Mechanical engineers in UMC-adopting jurisdictions design ventilation and equipment installations to its provisions instead of the IMC.
Used for: Requirements for solar thermal systems and hydronic heating and cooling systems.
How it’s used: Mechanical designers use it where adopted.
Used for: Requirements for pools, spas and hot tubs, including plumbing and equipment.
How it’s used: Pool designers and inspectors use it where adopted.
Used for: Requirements aimed at water efficiency and sanitation in buildings.
How it’s used: Designers use it for water-efficient plumbing design.
Used for: Requirements for plastic bathtubs, showers and other fixtures.
How it’s used: Specifiers use it to select listed plastic fixtures.
Model building, residential, fire, and plumbing codes adopted by U.S. jurisdictions.
Used for: The model building code most U.S. jurisdictions adopt (with amendments) as their base building code — occupancy classification, construction type, fire-resistance ratings, and structural-code cross-references.
How it’s used: Architects and engineers determine occupancy group and construction type early in design, since nearly every other code requirement (egress, fire rating, allowable area) flows from those two IBC classifications.
Used for: A stand-alone code for one- and two-family dwellings and townhouses, covering structural, mechanical, electrical, and plumbing provisions in one combined document.
How it’s used: Residential designers and builders work directly from the IRC rather than the IBC/NEC/IMC/IPC separately, since it's written as a simplified, prescriptive single-family code.
Used for: Model code for HVAC and mechanical systems — equipment installation, ventilation, and exhaust requirements.
How it’s used: Mechanical engineers design ventilation and equipment installations to satisfy the IMC as adopted locally, working alongside ASHRAE 62.1 which the IMC often references for ventilation rates.
Used for: Model code for water supply, drainage, and venting systems in buildings.
How it’s used: Plumbing engineers size fixture units, drainage, and venting to it (or to the competing Uniform Plumbing Code, depending on jurisdiction).
Used for: Model code addressing fire prevention and life safety in existing and new buildings — fire department access, hazardous materials storage, and fire protection system maintenance.
How it’s used: Fire protection engineers and AHJs use it alongside NFPA standards for ongoing fire-safety compliance, fire department access/water supply requirements, and hazmat storage limits.
Used for: Minimum energy efficiency requirements for the building envelope, lighting and mechanical systems in residential and commercial buildings.
How it’s used: Designers and code officials use it for energy code compliance, often with ASHRAE 90.1 as an alternative for commercial buildings.
Used for: Installation of fuel gas piping, appliances and venting.
How it’s used: Mechanical and plumbing designers size gas piping and vents to it.
Used for: Requirements for repairs, alterations, additions and change of occupancy in existing buildings.
How it’s used: Designers use it to decide how much of an existing building must be upgraded.
Used for: Design criteria for tornado and hurricane shelters.
How it’s used: Structural engineers design shelters to it.
International standards for electrical, electronic, and related technologies.
Used for: The international counterpart to the NEC — wiring rules, protection against electric shock, and installation requirements for low-voltage electrical systems, used throughout Europe and much of the rest of the world.
How it’s used: Electrical designers on non-U.S. projects size circuits and protection devices to it instead of the NEC; multinational firms need to know which of the two a given project falls under.
Used for: A standardized communication protocol and data model for substation automation — how protective relays, IEDs, and SCADA systems exchange data.
How it’s used: Substation and protection engineers specify IEC 61850-compliant relays and configure their communication mapping so devices from different manufacturers interoperate on the same substation network.
Used for: The base functional-safety standard behind Safety Integrity Levels (SIL) for safety-instrumented systems in industrial process control.
How it’s used: Process safety and controls engineers use it to determine the required SIL for a safety function (e.g., an emergency shutdown loop) and to select certified hardware that meets that SIL.
Used for: Cybersecurity requirements for industrial automation and control systems (IACS) — network zoning/segmentation, security levels, and secure product development lifecycle.
How it’s used: OT/ICS security engineers use its zone-and-conduit model to segment a plant network and assign target security levels to each zone, then select equipment certified against its component requirements.
Used for: Design verification and testing requirements for low-voltage switchboards and motor control center assemblies.
How it’s used: Switchgear manufacturers and panel builders verify a design to it (by test or by calculation) before labeling an assembly as compliant, and specifying engineers reference it in switchgear procurement specs.
Used for: Requirements for low-voltage breakers, contactors, motor starters, switches and control devices.
How it’s used: Panel designers select devices rated under the relevant part of the series.
Used for: The specifications for PLCs, including the five standard programming languages in part 3.
How it’s used: Automation engineers write and review PLC programs in ladder, function block, structured text and the other languages it defines.
Used for: Electrical safety and control requirements for machines used internationally.
How it’s used: Machine builders use it for disconnects, protective bonding, emergency stop circuits and control circuit design.
Used for: The IP code that rates an enclosure against solid objects and water.
How it’s used: Specifiers choose an IP rating such as IP54 or IP66 for equipment locations.
Used for: A family of standards on emission and immunity limits, test methods and mitigation of electromagnetic interference.
How it’s used: Product designers and test labs use it to qualify equipment for EMC compliance.
Used for: The base safety standard for medical electrical equipment, including leakage current limits and applied part types.
How it’s used: Medical device engineers design and test equipment to it, with particular standards covering specific device types.
Used for: The development, maintenance and risk-management processes for software in medical devices.
How it’s used: Software teams classify their software by safety class and apply the matching process rigor.
Electrical, electronics, and communications engineering practice standards.
Used for: The engineering calculation method behind an arc-flash study — incident energy and arc-flash boundary as a function of system voltage, bolted fault current, and clearing time.
How it’s used: Power system engineers feed one-line diagram and protective-device coordination data into its equations (or arc-flash software implementing them) to produce the incident-energy values that ultimately drive NFPA 70E PPE labeling.
Used for: Limits on harmonic voltage and current distortion at the point of common coupling between a facility and the utility grid.
How it’s used: Power quality engineers evaluate a facility's nonlinear loads (VFDs, UPS systems, rectifiers) against its distortion limits and specify harmonic filters or mitigation when a design would otherwise exceed them.
Used for: Design, testing, and application requirements for power and distribution transformers — loading guides, insulation levels, and test procedures.
How it’s used: Substation and power engineers use it to select transformer ratings, insulation class, and loading limits, and to specify factory acceptance test requirements in procurement documents.
Used for: The physical- and data-link-layer specifications behind wired Ethernet (802.3) and Wi-Fi (802.11) networking.
How it’s used: Network and telecommunications designers reference these to select cabling categories, switch port speeds, and wireless access point specifications that guarantee interoperability across vendors.
Used for: Technical requirements for connecting distributed generation (solar PV, battery storage, backup generation) to the utility grid — voltage/frequency ride-through, anti-islanding, and protection settings.
How it’s used: Solar and power-systems engineers design grid-interconnection protection schemes to it, and utilities require conformance as a condition of approving an interconnection application.
Used for: Methods for designing substation grounding grids so touch and step voltages stay within safe limits.
How it’s used: Substation engineers calculate grid resistance and tolerable voltages with its equations.
Used for: Guidance on protective devices and how to coordinate them in industrial and commercial power systems.
How it’s used: Engineers use it for relay and breaker settings and time-current coordination studies.
Used for: Ratings, testing and application of high-voltage and medium-voltage circuit breakers, switchgear and protective relays.
How it’s used: Engineers specify breaker ratings and relay requirements against the relevant C37 document.
Used for: Definitions of power quality events such as sags, swells, interruptions and transients, and how to monitor them.
How it’s used: Power quality investigators classify recorded events with its terminology.
Used for: A method for sizing stationary lead-acid battery banks from the load profile, duty cycle and design margins.
How it’s used: Engineers size substation and UPS batteries with its worksheets.
Used for: The standard for VLAN tagging and bridging in Ethernet networks.
How it’s used: Network designers segment traffic into VLANs and configure trunk links to it.
Used for: The DNP3 protocol used between SCADA masters and outstations in electric, water and other utilities.
How it’s used: SCADA engineers configure DNP3 points and secure links based on it.
Internet protocol standards (TCP/IP, DNS, and related RFCs).
Used for: The core specifications defining how packets are addressed and routed across IP networks.
How it’s used: Network engineers design IP addressing schemes and subnetting following these specifications for both legacy IPv4 and newer IPv6 network designs.
Used for: The protocol standard for automatic IP address assignment on a network.
How it’s used: Network engineers configure DHCP servers and scopes conforming to this RFC when designing automatic address assignment for a facility network.
Used for: The specification of TCP, the reliable transport protocol used by most applications.
How it’s used: Network and software engineers use it for how connections are set up, sequenced and closed.
Used for: The connectionless transport protocol used by DNS queries, streaming and many industrial protocols.
How it’s used: Developers choose it where low latency matters more than guaranteed delivery.
Used for: The shared meaning of HTTP methods, status codes and headers across HTTP versions.
How it’s used: Web and API developers rely on it for correct behavior.
Used for: The protocol that encrypts most web and many industrial connections.
How it’s used: Security engineers require it to protect data in transit.
Used for: How the Domain Name System resolves names to addresses.
How it’s used: Network engineers use it when designing and troubleshooting DNS.
Used for: The routing protocol that connects networks across the internet.
How it’s used: Service providers and large enterprises use it to exchange routes.
Used for: A link-state routing protocol used inside networks.
How it’s used: Network engineers use it in large enterprise and campus networks.
Used for: How devices synchronize their clocks over a network.
How it’s used: Engineers use it for log correlation and time-sensitive systems.
Used for: The framework for delegated access to resources.
How it’s used: Developers use it for API authorization.
Used for: The private IPv4 address ranges (10/8, 172.16/12, 192.168/16).
How it’s used: Network designers use these ranges inside plants and offices.
Used for: The architecture for securing IP traffic with IPsec.
How it’s used: Security engineers use it for site-to-site and remote access VPNs.
Used for: A compact format for signed claims, widely used for API authentication.
How it’s used: Developers use JWTs for sessions and API tokens.
Printed circuit board and electronics assembly standards.
Used for: Baseline PCB design rules — trace spacing, current-carrying capacity, and via requirements.
How it’s used: PCB layout engineers use its current-vs-trace-width charts to size copper traces for a given current and temperature rise before routing a board.
Used for: The most widely used workmanship standard for inspecting soldered electronic assemblies — defines what counts as an acceptable vs. defective solder joint or component placement.
How it’s used: Electronics manufacturers and quality inspectors reference its class-based (Class 1/2/3) acceptance criteria to accept or reject assembled boards during inspection.
Used for: Soldering process requirements — materials, methods, and verification criteria for producing the assemblies IPC-A-610 later inspects.
How it’s used: Manufacturing engineers set up and qualify a soldering process (reflow profile, flux selection) against it, often as a prerequisite to J-STD-001 operator certification.
Used for: Charts and methods for estimating trace temperature rise from current, copper weight and board conditions.
How it’s used: Layout engineers use it, usually in place of the older IPC-2221 chart, to size power traces.
Used for: Acceptance and performance requirements for bare rigid printed boards.
How it’s used: Fabricators and buyers cite it to define board quality classes.
Used for: A naming convention and method for the footprints (land patterns) of surface-mount components.
How it’s used: Library creators and layout engineers build footprints to it.
Used for: Visual acceptance criteria for bare boards.
How it’s used: Inspectors use it to accept or reject fabricated boards.
Used for: An open data format for sending a board design to fabrication and assembly.
How it’s used: Design teams use it as an alternative to Gerber files.
Used for: The moisture sensitivity levels that tell how long parts can sit before reflow.
How it’s used: Assemblers handle and bake parts based on their moisture sensitivity level.
Industrial automation, process control, and instrumentation standards.
Used for: The standardized symbol and tag-numbering system used on Piping and Instrumentation Diagrams (P&IDs) — how a transmitter, valve, or controller is drawn and tagged.
How it’s used: Instrumentation and controls engineers use its symbol library and tag-numbering convention (e.g., FT-101 for a flow transmitter) so P&IDs are readable consistently across a project and industry.
Used for: The process-industry-specific application of functional safety (SIL) concepts to safety instrumented systems (SIS) — emergency shutdown and safety interlock design.
How it’s used: Process safety engineers perform a SIL determination (via LOPA or similar) and design the safety instrumented function's sensor/logic-solver/final-element architecture to meet that target SIL.
Used for: A lifecycle framework for designing, rationalizing, and managing process-control alarm systems to avoid alarm flooding and nuisance alarms.
How it’s used: Controls engineers run an alarm rationalization exercise against its methodology to set priority, setpoints, and suppress redundant alarms in a DCS/SCADA system.
Used for: Models and terminology for batch process control.
How it’s used: Process engineers structure batch recipes and equipment control with it.
Used for: A model for connecting business systems with plant control systems.
How it’s used: Integrators use it to define interfaces between MES, ERP and control.
Used for: Guidance on designing consistent, effective operator interfaces.
How it’s used: Control system designers build HMI graphics and navigation from it.
Used for: Equations for sizing control valves.
How it’s used: Instrument engineers size control valves with it.
Used for: Classification of corrosive environments for control equipment.
How it’s used: Engineers select equipment protection and coating from the severity level.
Used for: Symbols for documenting binary logic.
How it’s used: Used for interlock and sequence documentation.
Industrial automation and control systems (OT) cybersecurity standards.
Used for: Defines system-level security requirements and the security-level (SL 1-4) target framework for industrial automation and control systems.
How it’s used: OT security engineers assign target security levels to network zones and verify that the deployed architecture meets each zone's SL-T requirements.
Used for: Component-level security requirements for individual devices (PLCs, HMIs, network equipment) used in industrial control systems.
How it’s used: Equipment vendors certify individual components against 62443-4-2, and OT engineers specify certified components when procuring new control-system hardware.
Used for: The vocabulary and models used across the series, such as zones and conduits.
How it’s used: Teams start here to learn the common terms.
Used for: The security management program an asset owner needs.
How it’s used: Plant owners build their OT security program from it.
Used for: Security capabilities required of integrators and service providers.
How it’s used: Owners ask integrators to meet it in contracts.
Used for: The risk assessment that defines zones, conduits and target security levels.
How it’s used: Engineers use it to segment a plant and set target levels.
Used for: The secure development process required of product suppliers.
How it’s used: Vendors certify their development process against it.
International standards spanning quality, environmental, safety, and industry-specific practice.
Used for: A generic quality-management-system framework applicable to any organization — document control, corrective action, and continual improvement processes.
How it’s used: Manufacturing and engineering firms certify their quality management system to ISO 9001, often a prerequisite for being an approved supplier to larger customers.
Used for: A framework for managing an organization's environmental impact and regulatory compliance obligations.
How it’s used: Facilities and engineering firms implement and certify an EMS to it as part of corporate sustainability programs or customer/contract requirements.
Used for: A framework for establishing, implementing, and maintaining an information security management system.
How it’s used: IT and OT security teams certify against it to demonstrate a structured security program, often required by enterprise customers or cyber-insurance underwriters.
Used for: A quality-management-system standard specific to the design and manufacture of medical devices.
How it’s used: Medical device engineering firms certify to it as part of the regulatory pathway (alongside FDA requirements) for bringing a device to market.
Used for: Functional-safety lifecycle requirements for electrical/electronic systems in production automobiles — the automotive-specific version of the IEC 61508 functional-safety concept.
How it’s used: Automotive electronics engineers determine an Automotive Safety Integrity Level (ASIL) for a vehicle function and design the hardware/software to meet that ASIL's process and architectural requirements.
Used for: Requirements for a management system for workplace health and safety.
How it’s used: Organizations certify their safety programs to it.
Used for: Requirements for a management system for energy performance.
How it’s used: Plants use it to set and track energy performance.
Used for: Principles and guidelines for managing risk in any organization.
How it’s used: Organizations use it as a general risk management framework.
Used for: Information management processes for building information modeling.
How it’s used: Project teams define how BIM data is exchanged with it.
Used for: The principles and terminology of asset management systems.
How it’s used: Asset owners use it to structure maintenance and lifecycle planning.
Used for: A method for assessing machine risk and choosing protective measures.
How it’s used: Machine designers use it to carry out risk assessments.
Used for: Performance levels (PL a to e) for the safety functions of machine controls.
How it’s used: Controls engineers design and verify safety functions with it.
Used for: The ISO system for geometric tolerances on drawings, comparable to ASME Y14.5.
How it’s used: Designers and inspectors use it where drawings follow ISO.
Used for: Default tolerances for dimensions when none are given on the drawing.
How it’s used: Drawings cite it in the title block.
Used for: Property classes such as 8.8 and 10.9 for metric fasteners.
How it’s used: Designers specify metric bolt classes from it.
Joint international information-technology and security standards, e.g. ISO/IEC 27001.
Used for: The internationally recognized certifiable standard for an information security management system.
How it’s used: Organizations pursue ISO/IEC 27001 certification to demonstrate a structured security program to customers, partners, and regulators — often required in enterprise vendor-risk assessments.
Used for: A standard for IT service management systems, covering how IT services are planned, delivered, and improved.
How it’s used: IT service organizations certify against it to formalize and benchmark their service-management processes, similar in spirit to ITIL but as a certifiable standard.
Used for: A catalog of information security controls that supports ISO/IEC 27001.
How it’s used: Security teams select and implement controls from it.
Used for: Guidance on risk management for an information security management system.
How it’s used: Risk managers use it with ISO/IEC 27001.
Used for: Extra security controls for cloud providers and customers.
How it’s used: Cloud teams use it to assess shared responsibility.
Used for: The framework used to evaluate the security of IT products.
How it’s used: Government buyers look for products evaluated under it.
Used for: Requirements for an organization's AI management system.
How it’s used: Organizations use it to govern AI development and use.
Used for: Requirements that testing and calibration labs must meet.
How it’s used: Labs are accredited to it, and buyers look for accredited labs.
Global telecommunications and radio-spectrum coordination standards.
Used for: International specifications for optical fiber characteristics and transmission performance used in telecommunications and long-haul networking.
How it’s used: Telecommunications engineers select fiber types (single-mode/multimode) and design link budgets referencing these specifications for long-distance or carrier-grade fiber runs.
Used for: International coordination of radio-frequency spectrum use across countries, preventing cross-border interference.
How it’s used: RF and radio-communications engineers check ITU-R regional spectrum allocations (alongside national regulators like the FCC) before designing equipment for a given frequency band.
Used for: The common single-mode fiber used for long-distance links.
How it’s used: Fiber planners specify G.652 fiber.
Used for: The standard for GPON used in fiber-to-the-home networks.
How it’s used: Operators and equipment vendors build PON networks to it.
Used for: The standard voice codec used in telephony and VoIP.
How it’s used: VoIP engineers use it for uncompressed voice.
Used for: A widely used video compression standard.
How it’s used: Streaming and surveillance systems use it.
Used for: The successor to H.264 with better compression.
How it’s used: Video systems use it to save bandwidth and storage.
Used for: The format of the digital certificates used with TLS and PKI.
How it’s used: Security engineers manage certificates in that format.
Used for: Color and signal parameters for HDTV.
How it’s used: Video engineers use it for color spaces.
Semiconductor device and memory standardization.
Used for: Electrical and timing specifications for DDR memory generations (DDR4, DDR5) — pinout, signaling, and timing parameters.
How it’s used: Hardware and PCB engineers design memory-interface routing and timing budgets against the relevant JESD79 revision to ensure a board works with standard, interchangeable memory modules.
Used for: A family of standardized reliability and environmental stress tests for semiconductor components — thermal cycling, humidity, ESD.
How it’s used: Component and product-qualification engineers run JESD22 test procedures on new semiconductor parts to validate reliability before design-in.
Used for: The baseline set of stress tests used to qualify integrated circuits.
How it’s used: Semiconductor manufacturers and buyers use it for product qualification plans.
Used for: Test methods and board definitions for measuring the thermal resistance of IC packages.
How it’s used: Thermal engineers read and compare package thermal data prepared to it.
Used for: A high-speed serial link between data converters (ADC/DAC) and logic devices.
How it’s used: FPGA and high-speed converter designers build to it.
Used for: Specifications for low-power DRAM used in mobile and embedded systems.
How it’s used: System designers pair processors with LPDDR memory defined by it.
Used for: The interface and command set for eMMC flash storage.
How it’s used: Embedded designers use eMMC parts that follow it.
Used for: Defined workloads for measuring the endurance of solid-state drives.
How it’s used: Storage vendors and buyers compare drive endurance with them.
Manufacturing and performance standards for electrical equipment.
Used for: Defines the NEMA enclosure-type rating system (NEMA 1, 3R, 4, 4X, 12, etc.) describing an enclosure's protection against dust, water, and corrosion.
How it’s used: Electrical and controls engineers specify a NEMA rating for panels and enclosures based on the installation environment — NEMA 4X for a washdown food-processing area, NEMA 3R for outdoor equipment.
Used for: Performance, dimensional, and testing standards for AC and DC electric motors and generators — frame sizes, efficiency classes, and service-factor definitions.
How it’s used: Mechanical and electrical engineers select motors by NEMA frame size and design letter (B, C, D) to ensure physical and electrical interchangeability across manufacturers.
Used for: Performance and rating standards for motor starters, contactors, and overload relays used in industrial control panels.
How it’s used: Controls engineers size motor starters and overload relays to NEMA size ratings (NEMA size 1, 2, 3...) when the design calls for NEMA-rated rather than IEC-rated control components.
Used for: The configurations of plugs and receptacles, such as the 5-15 and 5-20 patterns, and their dimensions.
How it’s used: Designers specify the receptacle configuration that matches the voltage, current and equipment.
Used for: Construction and performance requirements for panelboards.
How it’s used: Specifiers use it alongside UL standards when writing panelboard specifications.
Used for: Ratings and test requirements for molded-case circuit breakers and their enclosures.
How it’s used: Engineers check interrupting ratings and applications against it.
Used for: Rating and application guidance for adjustable-speed drives, including operating conditions.
How it’s used: Engineers use it to select and apply VFDs.
Used for: Classification, load ratings and installation of metal cable tray.
How it’s used: Designers select tray load class and spans from it.
Used for: A method for measuring and rating the energy efficiency of distribution transformers.
How it’s used: Specifiers use it to compare transformer efficiency.
Fire, electrical, and life-safety codes such as NFPA 70 (NEC) and NFPA 72.
Used for: The baseline safety code for essentially all electrical wiring, equipment, and installation practice in the U.S. — conductor sizing, overcurrent protection, grounding and bonding, and equipment-specific rules for everything from dwellings to industrial plants.
How it’s used: Electrical engineers and designers size circuits, panels, and services to its tables and rules; electricians install to it; inspectors enforce whatever edition the local jurisdiction has adopted (often with amendments). It is revised on a 3-year cycle.
Used for: Design, installation, and testing requirements for fire alarm and signaling systems — detector spacing, notification appliance coverage (audible/visible), circuit survivability, and system testing intervals.
How it’s used: Fire alarm designers use its detector-spacing and notification-coverage tables to lay out devices on floor plans; technicians follow its inspection and testing schedules for ongoing code-required maintenance.
Used for: Design and installation requirements for automatic fire sprinkler systems — hazard classification, hydraulic calculation methods, and sprinkler spacing/coverage.
How it’s used: Fire protection engineers classify the occupancy hazard, then hydraulically calculate pipe sizing and sprinkler density against its design-area tables to produce a stamped sprinkler drawing set.
Used for: Means-of-egress, occupant load, and general fire-safety requirements for buildings, organized by occupancy type — assembly, business, healthcare, and more.
How it’s used: Architects and fire protection engineers calculate occupant load and required egress width/travel distance from it during early design, since it directly drives stair, corridor, and exit-door sizing.
Used for: Workplace electrical safety practice — arc-flash risk assessment, required PPE categories, and safe work procedures around energized equipment.
How it’s used: Facilities perform an arc-flash study against it to generate equipment labels showing incident energy and required PPE category before anyone works on or near that equipment energized.
Used for: The required inspection, testing and maintenance routines for sprinkler, standpipe, fire pump and related water-based systems.
How it’s used: Building owners and fire protection contractors schedule recurring inspections and keep records to it, and inspectors check those records.
Used for: Requirements for selecting, installing and testing fire pumps, their drivers, controllers and arrangement.
How it’s used: Designers size and arrange fire pumps to it, and commissioning agents run the acceptance tests it describes.
Used for: Performance, installation, testing and maintenance requirements for emergency and standby generator systems.
How it’s used: Electrical engineers classify the system, set start-time and fuel-runtime requirements, and facility staff follow its test schedule.
Used for: Requirements for gas and vacuum systems, electrical systems, and risk categories in hospitals and other health care facilities.
How it’s used: Hospital designers and engineers use its risk categories to decide how robust each system and room must be.
Used for: Storage, handling and use of flammable and combustible liquids, including container, tank and room requirements.
How it’s used: Process and fire protection engineers use it to classify liquids and set storage limits, ventilation and separation.
Used for: Requirements for siting, spacing, protection and hazard mitigation of stationary battery energy storage systems.
How it’s used: Designers and authorities use it for battery room layout, fire detection and suppression, and explosion control decisions.
Used for: Electrical requirements for the control equipment, wiring and safeguarding of industrial machines.
How it’s used: Machine builders and panel shops design machine controls, disconnects and emergency stops to it.
Used for: Requirements for air terminals, down conductors, grounding and bonding that protect structures from lightning.
How it’s used: Designers lay out lightning protection and verify bonding to other grounding systems against it.
U.S. federal standards body; publishes the Cybersecurity Framework and measurement standards.
Used for: A risk-based framework (Identify, Protect, Detect, Respond, Recover) for organizing an organization's cybersecurity program, including OT/ICS environments.
How it’s used: Security engineers and CISOs map existing controls against its five functions to identify gaps and prioritize a cybersecurity roadmap, often as the top-level framework tying together more prescriptive standards like IEC 62443.
Used for: A detailed catalog of security controls used primarily for U.S. federal information systems and increasingly by private-sector compliance programs.
How it’s used: Security engineers on federal or federally-adjacent projects select and implement controls from its catalog to satisfy FISMA or contractual security requirements.
Used for: Security guidance specific to industrial control systems and OT environments, addressing the ways OT security differs from conventional IT security.
How it’s used: OT/ICS security engineers use it alongside IEC 62443 as guidance for securing SCADA, DCS, and PLC-based control networks without disrupting real-time control functions.
Used for: A method for assessing information security risk.
How it’s used: Risk analysts use it to structure assessments.
Used for: The steps of the Risk Management Framework, from categorizing to monitoring systems.
How it’s used: Federal systems and contractors follow it to authorize systems.
Used for: The phases of incident response and how to prepare.
How it’s used: Response teams build their plans from it.
Used for: Requirements for identity proofing, authentication and federation.
How it’s used: Designers use it for password and multi-factor authentication policy.
Used for: Security requirements for contractors that handle controlled unclassified information.
How it’s used: Defense and federal contractors assess themselves against it.
Used for: The concepts and components of zero trust architecture.
How it’s used: Architects use it to plan zero trust programs.
Used for: Requirements and validation for cryptographic modules.
How it’s used: Procurement requires validated modules for government use.
Used for: The AES encryption algorithm.
How it’s used: It is the standard symmetric cipher used almost everywhere.
Aviation and aerospace systems standards, notably software/hardware assurance (DO-178C, DO-254).
Used for: The standard aviation regulators (FAA, EASA) recognize for certifying software used in airborne systems, tied to a Design Assurance Level (DAL) based on failure-condition severity.
How it’s used: Avionics software engineers develop and verify software following its DAL-specific process objectives, producing the certification evidence required for FAA/EASA approval.
Used for: The hardware counterpart to DO-178C — design assurance requirements for complex airborne electronic hardware (FPGAs, ASICs, custom circuit boards).
How it’s used: Avionics hardware engineers apply its design-assurance-level process to custom hardware design and verification as part of the same airborne-system certification package.
Used for: The environmental tests for airborne equipment, such as temperature, vibration and lightning.
How it’s used: Equipment makers qualify avionics to it.
Used for: The process for handling cybersecurity in airworthiness.
How it’s used: Aircraft and avionics programs use it with DO-356A.
Used for: Guidance for avionics platforms that host several functions.
How it’s used: IMA suppliers and integrators use it for certification planning.
Used for: How to qualify the tools used in airborne software development.
How it’s used: Tool vendors and programs use it to qualify tools.
Used for: Requirements for ADS-B Out transmitters.
How it’s used: Avionics manufacturers use it to design ADS-B equipment.
Used for: Requirements for GPS receivers used in navigation.
How it’s used: Avionics manufacturers use it for GPS and WAAS receivers.
Automotive, aerospace, and commercial vehicle engineering standards.
Used for: The CAN-bus-based communication protocol used across heavy-duty vehicle and off-highway equipment networks — engine, transmission, and body-control-module data.
How it’s used: Automotive and off-highway electronics engineers implement J1939-compliant messaging so ECUs from different suppliers can share data on the same vehicle network.
Used for: The aerospace-industry-specific quality-management-system standard, built on ISO 9001 with additional aerospace requirements (configuration management, first-article inspection).
How it’s used: Aerospace manufacturers and their suppliers certify to AS9100 as a near-universal prerequisite for supplying parts into the commercial or defense aerospace supply chain.
Used for: Grade classification (Grade 5, Grade 8, etc.) defining the material and mechanical properties of bolts and threaded fasteners.
How it’s used: Mechanical engineers specify fastener grade on drawings to ensure the correct strength class is used in a bolted-joint calculation.
Used for: The connector and communication standard for AC charging of electric vehicles in North America.
How it’s used: EVSE designers and installers use it for connectors and signaling.
Used for: The levels of driving automation, from 0 to 5.
How it’s used: The industry and regulators use its levels to describe vehicle automation.
Used for: The diagnostic services used by on-board diagnostics for emissions-related data.
How it’s used: Scan tools and shops read vehicle data through it.
Used for: A development assurance process for aircraft and their systems.
How it’s used: Aerospace programs use it with DO-178C and DO-254.
Used for: Methods such as FHA, FTA and FMEA for aircraft safety assessment.
How it’s used: Safety engineers use it for system safety analyses.
Used for: Requirements for furnace temperature control and measurement in heat treating of aerospace parts.
How it’s used: Heat-treat shops use it for furnace classification and surveys.
Ductwork construction and installation standards.
Used for: Duct gauge, reinforcement, and joint-construction requirements by duct pressure class (low, medium, high pressure).
How it’s used: Mechanical engineers specify a SMACNA pressure classification on drawings, and duct fabricators build to its gauge/reinforcement tables for that pressure class rather than re-engineering each duct run from scratch.
Used for: Construction standards for heavier-duty industrial exhaust and process ductwork beyond typical commercial HVAC pressure classes.
How it’s used: Industrial ventilation engineers reference it for process exhaust systems handling higher pressures, temperatures, or corrosive airstreams than standard commercial ductwork.
Used for: Construction details for round industrial and exhaust duct.
How it’s used: Industrial ventilation engineers specify gauges and reinforcement from it.
Used for: Methods for testing duct leakage and the leakage classes.
How it’s used: Testing and balancing contractors run leakage tests to it.
Used for: Guidance on bracing ducts, pipes and equipment against earthquakes.
How it’s used: Designers detail seismic restraints for mechanical systems from it.
Used for: Details for roofing, flashing and exterior sheet metal.
How it’s used: Architects and contractors use its details for weathertight sheet metal work.
Structured cabling and telecommunications infrastructure standards.
Used for: Cable category performance requirements and structured-cabling topology for commercial buildings — the same standard co-published with ANSI, above.
How it’s used: Structured cabling designers use it to select cable category and design horizontal/backbone cabling topology, patch panel layout, and telecom room sizing.
Used for: Design requirements for the physical spaces (telecom rooms, cable pathways, conduit sizing) that house structured cabling infrastructure.
How it’s used: Telecommunications and architectural designers size telecom/IDF room dimensions and cable-tray/conduit fill from its requirements during building design.
Used for: Data center infrastructure design — tiered redundancy classification (comparable in concept to the Uptime Institute's Tier system), cabling, and physical security.
How it’s used: Data center designers use its tiered-redundancy framework and cabling/pathway requirements when scoping a new data center or colocation facility's infrastructure.
Used for: Labeling and documentation of cabling, pathways and spaces.
How it’s used: Installers label cables and keep records to it.
Used for: Bonding and grounding for telecommunications systems.
How it’s used: Designers specify the telecommunications grounding busbar and bonding.
Used for: The color code for fibers and fiber cable jackets.
How it’s used: Installers identify fibers and fiber types by color.
Used for: Procedures for testing installed fiber, such as loss measurement.
How it’s used: Technicians certify fiber links with these methods.
Used for: Cabling requirements for industrial environments.
How it’s used: Plant network designers use it for industrial Ethernet cabling.
Used for: Cabling and pathways between buildings on a campus.
How it’s used: Campus designers use it for outside plant design.
Used for: Cabling for homes and small residential buildings.
How it’s used: Installers use it for home networks.
Product safety testing, certification, and listing standards.
Used for: Construction and evaluation requirements for industrial control panels — wire sizing, short-circuit current rating (SCCR), component spacing, and marking.
How it’s used: Panel shops build and label control panels to UL 508A so the finished panel can carry a UL listing mark, which many AHJs and end customers require before a panel can be energized.
Used for: Safety and performance testing for molded-case circuit breakers, including their interrupting rating.
How it’s used: Electrical engineers select breakers with a UL 489 interrupting (AIC) rating that meets or exceeds the calculated available fault current at that point in the system.
Used for: Safety and performance testing for surge protective devices (SPDs) — the same listing the 2023/2026 NEC now requires for new dwelling-unit services.
How it’s used: Electrical designers specify a UL 1449-listed SPD, Type 1 or Type 2 as applicable, at the service equipment to satisfy NEC 230.67.
Used for: A flammability-rating classification for plastics (V-0, V-1, V-2, HB) used in electronic and electrical products.
How it’s used: Electronics and product designers select enclosure and PCB materials rated to a specific UL 94 class to meet the fire-safety requirements of the end product's overall UL listing.
Used for: Safety requirements for information-technology and audio/video equipment — the standards behind most consumer and IT-equipment safety certification (62368-1 has superseded 60950-1).
How it’s used: Electronics manufacturers design and test products to it before they can bear a UL safety mark for sale in the U.S. market.
Used for: Listing requirements for fire alarm control panels and related equipment.
How it’s used: Designers specify listed panels; AHJs expect fire alarm equipment to carry this listing.
Used for: Performance and listing requirements for smoke detectors used on fire alarm systems.
How it’s used: Engineers specify listed detectors for the application and spacing.
Used for: Safety and grid-interconnection requirements for inverters used with solar, storage and other generation.
How it’s used: Solar and storage designers specify listed inverters; utilities often require the listing for interconnection.
Used for: Safety requirements for energy storage systems as a complete assembly.
How it’s used: Designers and authorities look for it, together with UL 9540A fire testing, when approving battery systems.
Used for: Safety requirements for batteries used in stationary and auxiliary power applications.
How it’s used: Battery system designers specify cells and modules evaluated under it.
Used for: Construction and testing requirements for dead-front switchboards.
How it’s used: Specifiers and switchgear manufacturers use it for listed switchboards.
Used for: Requirements for equipment that switches emergency lighting on when normal power fails.
How it’s used: Designers specify listed relays and controls for egress lighting.
Used for: Performance requirements for AFCI devices that detect dangerous arcing.
How it’s used: Electricians and designers use listed AFCIs where the electrical code requires them.