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Research draft

seat belt

vr.tr.seat-belt · PHY.OBJ

Enable an AI agent to recognise a seat belt, record its installation and condition, and determine whether use, adjustment, inspection or replacement is appropriate from available evidence.

Thing Registry Physical world and living systems

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

Researched by: Codex + Grok

Purpose and description

Enable an AI agent to recognise a seat belt, record its installation and condition, and determine whether use, adjustment, inspection or replacement is appropriate from available evidence.

A seat belt is a load-bearing occupant-restraint assembly of webbing, buckle, retractor and structural anchorages that couples a seated person to a vehicle or machine so crash or upset deceleration is taken through the pelvis and, in three-point and multi-point designs, the shoulder girdle, rather than by unrestrained impact with the interior.

It can be Identify the assembly and check its documented compatibility with a seating position.; Record fastening, release and adjustment observations using applicable instructions.; Assess routing and fit for a specified occupant and seating configuration.; Document component condition and request an appropriate inspection when evidence is incomplete.; Determine whether continued use is supported by recorded criteria and history.; Identify the required replacement assembly and installation procedure when replacement is indicated..

Distinguishing features

Its documented function is restraining an occupant at a seating position during vehicle motion or an impact, rather than securing cargo or arresting a fall.

Its restraint path connects occupant-contacting straps through a fastening arrangement to designated seat or vehicle attachment interfaces.

A retractor is not required for identification: a manually adjusted lap belt can still meet the functional and installation tests.

Webbing, a buckle or a retractor alone is a component; the record must distinguish a complete seat-belt assembly from a detached part.

For ambiguous harnesses or positioning straps, intended use and installation documentation determine classification rather than appearance alone.

Scope

+ Belt configuration and the seating position it serves

+ Webbing, latch plate, buckle, adjusters and any retractors or integrated restraint devices

+ Attachment interfaces, routing and installation compatibility

+ Fastening, adjustment, payout, retraction and locking states where applicable

+ Observable damage, event history and evidence supporting serviceability

+ Applicable instructions and constraints on use, maintenance and replacement

- The vehicle's overall crashworthiness and complete occupant-protection system

- Seat structure and vehicle-body anchorage engineering beyond the belt's attachment requirements

- Occupant anatomy, medical condition and injury assessment

- Child restraint assemblies and their internal harnesses

- Airbag assemblies and vehicle restraint-control electronics

- Cargo tie-downs, fall-arrest harnesses and mobility positioning straps

Characteristics

Assembly identity
Manufacturer, part number, variant and identifying label information; unknown permitted Connects the physical assembly to compatibility information, instructions and notices.
Restraint configuration
Lap-only, diagonal-only, combined lap-and-diagonal, multipoint or unresolved Identifies the intended restraint path and the components that should be present.
Served seating position
Link to vehicle and seat position, including orientation where known Prevents treating similar-looking assemblies as interchangeable across positions.
Installed component set
Linked webbing, latch plate, buckle, adjusters, retractors and other fitted devices Supports completeness checks and identifies which component an observation concerns.
Usable adjustment range
Millimetres of available length or travel, with configuration and measurement method Records whether the assembly can achieve its documented routing and adjustment.
Fastening state
Unfastened, apparently latched, engagement verified by applicable procedure, release fault or unknown Separates visible insertion or a sensor indication from evidence of mechanical engagement.
Webbing movement state
Payout, retraction and locking observations recorded separately; not fitted and untested permitted Avoids interpreting every refusal to extend as damage or every free movement as correct operation.
Routing and fit state
Observed route, twist or obstruction locations, adjustment and fit assessment against applicable instructions A complete, fastened assembly may still be routed or adjusted incorrectly.
Condition observations
Component-specific damage, contamination, wear and alteration observations, with date and evidence Preserves the basis for inspection or replacement decisions without reducing condition to appearance.
Event and service history
Links to collision, restraint activation, installation, inspection and maintenance records Relevant history may affect permitted actions even when visible damage is absent.
Serviceability determination
Undetermined, awaiting inspection, accepted under identified criteria or rejected under identified criteria Keeps a decision tied to its evidence, authority and applicable configuration.

Also called

seat belt airbagcar seatbeltfive-point harness

Where this came from

wikidata · CC0 1.0

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.

Restraint identity and boundary Establishes what seat belt is being represented and where its assembly boundary lies.

Appearance alone cannot establish intended restraint use, assembly completeness or interchangeability.

Intended restraint role

Distinguishes a seat belt from similar straps and harnesses.

Seat-occupant restraint identity

Record evidence that the item is intended to restrain an occupant at a vehicle seating position.

  1. What intended use identifies this item as a seat belt rather than a cargo restraint, fall-arrest harness or positioning strap? definition
  2. Which label, manufacturer document or installation record supports that identification? provenance

Assembly membership

Defines the represented assembly and its constituent restraint components.

Component and variant boundary

Record the belt configuration, identifying variant and components included in this assembly record.

  1. Which webbing sections, latch plates, buckles, adjusters and fitted devices belong to this assembly? boundary
  2. Does the record represent a complete restraint assembly, a replacement subassembly or an unidentified collection of parts? definition
Installation and attachment Records the seating position, mounting interfaces and installed restraint path.

A seat belt's suitability depends on its specific installation, including matched components and attachment geometry.

Seating-position compatibility

Links the assembly to the position and configuration for which it is intended.

Documented installation match

Record the evidence matching the belt variant and mating components to the installed seating position.

  1. For which vehicle, seating position and seat configuration is this belt variant documented as suitable? boundary
  2. What evidence confirms that the installed buckle and latch plate are the specified mating components? provenance

Mounting and belt path

Captures attachment interfaces and routing through guides or adjusters.

Installed path and attachment evidence

Record where the assembly attaches, how webbing is routed and which installation checks have supporting evidence.

  1. Where are the belt's attachment interfaces, guides and adjustable mounting points relative to its seating position? boundary
  2. Which applicable installation checks have been completed, by whom and against which instructions? provenance
Occupant routing and fastening Represents the belt's current interaction with an occupant and its fastening mechanism.

Occupancy, latch indication and suitable restraint fit are separate observations that must not be conflated.

Occupant belt fit

Records the observed restraint route and adjustment for a particular use configuration.

Routing and adjustment observation

Record webbing placement, twists, obstructions and available adjustment against the applicable fit guidance.

  1. How is the webbing routed across the occupant and through any guides, and where are twists, slack or obstructions observed? measurement
  2. Which adjustments are permitted by the instructions for this occupant and seating configuration? action

Latch and release

Separates mechanical fastening observations from electrical indications.

Engagement and release evidence

Record latch engagement, release operation and any buckle-status indication with their verification methods.

  1. What evidence establishes the current mechanical engagement state, and is a buckle sensor indication recorded separately? measurement
  2. Does the buckle release as specified under the applicable checking procedure, or is its operation untested or faulty? measurement
Webbing control and restraint devices Records how belt length is managed and which additional restraint mechanisms are fitted.

Retractors, manual adjusters and other restraint devices require configuration-specific interpretation of their observed states.

Length management

Captures manual adjustment or retractor behaviour without assuming every belt uses the same mechanism.

Adjustment, payout and locking

Record the fitted length-control mechanism and observations made under identified conditions.

  1. What manual adjuster or retractor type is documented, and which operating modes are applicable? definition
  2. What adjustment, payout, retraction and locking behaviour was observed, under which procedure and installation conditions? measurement

Additional restraint mechanisms

Identifies fitted devices such as pretensioners or load limiters and their evidence requirements.

Fitted device status

Record documented device presence, known activation evidence and dependencies on external diagnostic records.

  1. Which additional restraint devices are documented as part of this assembly, and which belong to neighbouring systems? boundary
  2. What inspection, event or diagnostic evidence establishes each fitted device's status, and what remains unknown? provenance
Condition, history and disposition Connects physical observations and service history to supported decisions about use or intervention.

A belt can appear intact while its history or applicable instructions require further assessment.

Damage and event evidence

Preserves component-level condition observations and relevant historical uncertainty.

Inspection and history record

Record webbing, stitching, hardware and mechanism observations alongside collision, activation and alteration history.

  1. What cuts, fraying, stitching damage, contamination, deformation, corrosion or functional irregularities were observed, and on which components? measurement
  2. What is known about collision involvement, restraint activation, previous replacement or modification, and which records support it? provenance

Use and service decision

Records permitted next actions with their governing criteria and unresolved dependencies.

Evidence-based disposition

Record whether evidence supports use, further inspection or replacement, without treating missing evidence as a pass.

  1. Which applicable manufacturer instructions, inspection criteria or notices govern continued use and replacement for this exact assembly? provenance
  2. Given the recorded condition and history, what next action is supported, who may perform it and what evidence is still required? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.

A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.

Reported evidence

Findings from the breadth pass, kept separate from the structural claims.

Kinds and varieties

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Two-point lap belt
  • Three-point lap-and-shoulder belt with emergency-locking retractor (ELR)
  • Switchable ALR/ELR three-point belt used to cinch a child seat
  • Automatic (passive) belt: door-mounted or motorized shoulder belt, often with a separate lap belt
  • Inflatable seat belt (airbelt)
  • Multi-point competition or crew harness (four-, five- or six-point)
  • Integrated child harness or built-in child restraint
  • Off-highway operator belt on tractors, earth-movers and industrial trucks, often a two-point pelvic belt
  1. Which of these kinds and varieties hold for the sense of seat belt this model covers, and on what evidence? provenance

Identifiers and schemes

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Wikidata - Q200403 - Item for the vehicle occupant-restraint seat belt
  • Harmonized System (HS) - 8708.21 - Safety seat belts of a kind used for motor vehicles
  • UN Regulation No. 16 type approval - E-mark under R16 (E-circle plus approval number on the belt label) - Component approval mark on belts sold in 1958-Agreement markets
  • FMVSS 209 assembly type - Type 1 (pelvic only) or Type 2 (pelvic and upper torso) - U.S. regulatory classification of the assembly, not a serial number
  1. Which of these identifiers and schemes hold for the sense of seat belt this model covers, and on what evidence? provenance

Standards and regulation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • UNECE Regulation No. 16 - safety-belts and restraint systems (UNECE World Forum WP.29)
  • UNECE Regulation No. 14 - safety-belt anchorages (UNECE WP.29)
  • FMVSS No. 208 Occupant crash protection (NHTSA, 49 CFR 571.208)
  • FMVSS No. 209 Seat belt assemblies (NHTSA, 49 CFR 571.209)
  • FMVSS No. 210 Seat belt assembly anchorages (NHTSA, 49 CFR 571.210)
  • CMVSS 208/209/210 (Transport Canada)
  • ADR 4 Seatbelts (Australia, Department of Infrastructure)
  • GB 14166 Safety-belts, restraint systems and ISOFIX restraint systems (China)
  • ISO 3776 (agricultural tractors and machinery - seat-belt assemblies)
  • ISO 6683 (earth-moving machinery - seat belts and anchorages)
  1. Which of these standards and regulation hold for the sense of seat belt this model covers, and on what evidence? provenance

Real-world use

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Primary occupant restraint in passenger cars, light trucks, coaches and buses, worn over the pelvis and (when three-point) the outboard shoulder
  • Required passenger restraint on commercial aircraft, almost always a two-point lap belt; some general-aviation and crew seats use three-point or multi-point harnesses
  • Operator restraint on forklifts, agricultural tractors and earth-moving machines, mainly to keep the operator in the seat in a rollover rather than to manage a high-speed crash pulse
  • Motorsport and some military vehicles use four- to six-point harnesses with a crotch strap to control the pelvis
  • Vehicle three-point belts are the installation path for many belt-installed child seats; switchable ALR modes exist for that job
  • Buckle and webbing sensors drive seat-belt reminders and, in some vehicles, airbag suppression logic
  1. Which of these real-world use hold for the sense of seat belt this model covers, and on what evidence? provenance

Typical measurements

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Webbing width - 46-50 - mm
  • Type 1 (lap) assembly loop-load test - ≥22.2 - kN
  • ELR vehicle-sensitive lock threshold (UNECE R16) - 0.45-0.85 - g
  • Lap-belt anchorage angle to the horizontal - 30-80 - degree
  • Adaptive shoulder load-limiter force (passenger cars) - 2-6 - kN
  1. Which of these typical measurements hold for the sense of seat belt this model covers, and on what evidence? provenance

Failure modes and hazards

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Non-use, slack, twist, or wearing the shoulder run under the arm or behind the back, all of which raise occupant excursion
  • Submarining: the pelvis slides under a loose or poorly angled lap belt so load goes into the abdomen
  • Seat-belt syndrome: bowel, mesenteric or lumbar Chance-type injury from a concentrated lap-belt load
  • Webbing cut, abrasion at the D-ring, or UV/chemical degradation that lowers remaining strength
  • Retractor fails to lock in a crash, or locks spuriously in normal driving
  • Buckle not fully latched; pretensioner not replaced after a previous firing
  • Load limiter allows too much chest excursion into the airbag or interior
  • Adult three-point belt on a small child without a booster, with the webbing across the neck or soft abdomen
  1. Which of these failure modes and hazards hold for the sense of seat belt this model covers, and on what evidence? provenance

Regional variation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Spelling and legal title: U.S. regulations say "seat belt"; UK, Australian and New Zealand usage often writes "seatbelt" (e.g. ADR 4)
  • The United States uniquely required automatic/passive belts for a period under FMVSS 208 (1970s-1990s); that architecture was rare elsewhere
  • Rear-seat three-point fitment and wearing mandates arrived on different calendars; some older fleets still have a two-point centre-rear belt
  • Wearing laws are enforced as primary or secondary offences depending on jurisdiction
  • "Safety belt" survives in older U.S. legal and insurance language; Volvo's 1959 three-point design (Nils Bohlin) was released as an open patent and became the global default
  1. Which of these regional variation hold for the sense of seat belt this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Child restraint system (car seat / booster) - An add-on restraint sized for a child; it may be installed with the adult seat belt or ISOFIX, but it is not itself the vehicle belt
  • Airbag (supplemental inflatable restraint) - A pyrotechnic cushion that manages the second impact; it does not couple the occupant to the structure with webbing and is specified as supplemental to the belt
  • Fall-arrest or work-positioning harness - Personal protective equipment for height, governed by PPE standards (e.g. EN 361, ANSI Z359), not vehicle crash regulations
  • Cargo, recovery or tie-down webbing - Similar polyester webbing and hardware look; it is not an occupant restraint and is rated and labelled under cargo-lashing rules
  • Seat-belt reminder or buckle switch - An electrical sensor in or near the buckle; it reports use, it is not the load path
  1. Which of these neighbouring kinds and how to tell them apart hold for the sense of seat belt this model covers, and on what evidence? provenance

Sources

  1. Federal Motor Vehicle Safety Standard No. 209, Seat Belt Assemblies (49 CFR 571.209), National Highway Traffic Safety Administration - Type 1 vs Type 2 assemblies, webbing width, loop-load and hardware performance used for kinds, identifiers and measurements
  2. Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection (49 CFR 571.208), National Highway Traffic Safety Administration - When belts must be fitted, crash-protection role relative to airbags, and the U.S. automatic-belt chapter
  3. UN Regulation No. 16, Uniform provisions concerning the approval of safety-belts, restraint systems, child restraint systems and ISOFIX child restraint systems, United Nations Economic Commission for Europe (WP.29) - European type-approval of belts, ELR locking behaviour, and the E-mark identifier
  4. ISO 6683, Earth-moving machinery - Seat belts and seat belt anchorages, International Organization for Standardization - Operator belts on construction machinery as a distinct kind and regulatory track

What the second pass must settle

  • Does the registry intend this entry to cover aircraft belts and motorsport multipoint restraints as well as conventional road-vehicle belts?
  • Where should ownership fall for seat-integrated anchorages, buckle-mounted pretensioners and shared assemblies serving more than one seating position?
  • Which authoritative documents provide identification, compatibility and inspection criteria for the seat-belt variants this model will first cover?
  • Which observations and documented procedures can distinguish expected retractor locking from a fault for each supported mechanism?
  • How should serviceability remain unresolved when collision history, component identity or restraint-device activation status cannot be established?