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Overview

General comment

Production covered

USB4 Gen 3 / Thunderbolt 4 passive cable supporting 40 Gbps data transfer (two 20 Gb/s lanes) and up to 240 W USB Power Delivery 3.1 EPR - data, video, and charging power on one reversible USB-C connector. Passive 40 Gb/s certification limits length to 0.5-1.0 m (0.8 m typical); longer 40 Gb/s links require active cables with signal-boosting electronics. Coaxial construction with silver- plated copper conductors for reduced skin effect losses at high frequencies. Foil and braided shielding for EMI compliance. TPE jacket for premium feel.

Modelling choices

This dataset is modelled with no water reuse. No reclaim rate is published for this kind of plant, so the water shown is the full fresh intake and no recycling credit has been deducted from it.

Technology
High-Speed Data Cable Assembly, Universal Serial Bus
Geography
Global average data from equipment vendor specifications and industry literature

System boundary

System boundary - USB4 Cable PassiveSystem boundary figure: identity, gate in, entering flows, the dashed system boundary and the unit processes inside it, the reference product, emissions and waste, and below it the flows that are recorded but not quantified. No inventory quantities.USB4 Cable PassiveGATE INRaw materials and sub-componentsENTERING FLOWSElectricityWaterMaterialsSYSTEM BOUNDARYMODELLED PROCESS SEQUENCEProcess sequenceSilver Wire PlatingFEP Insulation ExtrusionFoil Shield ApplicationBraid Shield ApplicationTPE Jacket ExtrusionUSB-C Plug TerminationCable TestingCable twisting (twinaxial pair formation)REFERENCE PRODUCTUSB4 Cable PassiveAssembled and tested componentEMISSIONS AND WASTEEmissions to airEmissions to waterWaste routesRECORDED BUT NOT QUANTIFIEDIn scope, left out of the quantified inventoryCut off below the significance threshold, or with no background dataset available - each is listed with its reason3FLOWSsystem boundaryreference flowentering flowemission / waste

The figure groups this dataset's unit processes by class. It is not a count of manufacturing steps — each process runs over as many passes as the flow requires, and those pass counts ship with the dataset.

Download this figure (SVG)

Data quality and references

Composite DQI 2.1 Good
Reliability
2.9
Completeness
3.0
Temporal
1.0
Geographic
2.0
Technological
2.5

Pedigree scores follow the ecoinvent data-quality matrix: 1 is the best attainable, 5 the weakest. The composite is their aggregate.

Sampling procedure
Component vendor specifications, academic papers, industry literature
Coverage status
Partial
Pedigree-scored source files
8 — the source records behind this dataset's manufacturing operations. Each carries the five pedigree axes above; the composite DQI aggregates them.

Technosphere inputs

16 flows. Quantities are not published; they ship with the dataset on Circa.

Electricity, China (CN) ElectricitykWh · -37.2% / +77.5%
Derivation basis
  • Calculated from equipment energy across all manufacturing operations. This model includes no facility support, so the total is the manufacturing operations alone.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • Made-in-China WL-FSJ550 automatic cable coil shrink wrapping machine specifications
  • Srichand Engineering; Heng Hui; Shenzhen Adp braiding machine specifications
  • Komax Alpha 530 termination line specifications
  • Cirris 1100H+ User's Manual Version 4.7c, Cirris Systems Corporation
  • E5071C Network Analyzer Installation Guide, Keysight Technologies
Background data
ecoinvent 3.12
Background dataset
electricity, medium voltage
Uncertainty
-37.2% / +77.5% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kWh
Fresh water WaterL · ±25%
Derivation basis
  • Calculated from process-water and ultrapure-water demand across all manufacturing operations. This model includes no facility support, so the demand is the manufacturing operations alone. The fresh intake shown is that whole demand: the water-recycling scenario this dataset assumes reuses none of it, so nothing has been deducted, and wastewater follows the same balance.

No source is attached to this row.

Source citations
Not stated
Background data
ecoinvent 3.12
Background dataset
tap water
Notes
Process and cleaning water
Uncertainty
±25% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
L
Copper, cathode Materialkg · -15.4% / +20.3%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
copper, cathode
Notes
From Silver-plated copper (stranded) (98.0% copper material)
Uncertainty
-15.4% / +20.3% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Wire drawing, copper Materialkg · -15.4% / +20.3%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
wire drawing, copper
Notes
From Silver-plated copper (stranded) (98.0% copper wire drawing). Transformation activity - does NOT include copper material
Uncertainty
-15.4% / +20.3% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Silver Materialkg · -19.9% / +50%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
silver
Notes
From Silver-plated copper (stranded) (2.0% silver plating). Thin silver coating on stranded copper (skin-effect at GHz)
Uncertainty
-19.9% / +50% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
FEP (Fluorinated Ethylene Propylene) Materialkg
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
proxy-mapped
Background dataset
polyethylene, high density, granulate
Uncertainty
No range defined.
Unit
kg
Aluminum/PET laminate Materialkg
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
aluminium, wrought alloy
Uncertainty
No range defined.
Unit
kg
Tin Materialkg
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
tin
Notes
From Tinned copper braid (3.0% tin plating)
Uncertainty
No range defined.
Unit
kg
TPE (Thermoplastic Elastomer) Materialkg
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
proxy-mapped
Background dataset
styrene butadiene rubber, emulsion polymerised
Uncertainty
No range defined.
Unit
kg
Release liner Materialkg
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
polyethylene terephthalate, granulate, amorphous
Uncertainty
No range defined.
Unit
kg
Stainless Steel (SUS304) Materialkg · -18.8% / +25%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
steel, chromium steel 18/8, hot rolled
Uncertainty
-18.8% / +25% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
LCP (Liquid Crystal Polymer) Materialkg · ±25%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
proxy-mapped
Background dataset
glass fibre reinforced plastic, polyamide, injection moulded
Uncertainty
±25% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Phosphor Bronze (CuSn8) Materialkg · ±25%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
bronze
Uncertainty
±25% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Gold (Au) Materialkg · -50% / +100%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
gold
Uncertainty
-50% / +100% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Nickel (Ni) Materialkg · ±50%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
ecoinvent 3.12
Background dataset
nickel, class 1
Uncertainty
±50% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Sn/Ag/Cu Solder Materialkg · -30.6% / +38.9%
Derivation basis
  • Calculated from per-operation consumption, operation counts, and manufacturing yield.
  • REEL derivation: engineering estimate of cable and interconnect component mass and material split, built from vendor catalogue and product-page data for representative parts; no single published inventory covers this component class

The sources for this row are listed below.

Source citations (dataset-level)
  • USB Promoter Group USB4 Version 2.0 announcement; Intel Thunderbolt certified passive-cable listings
  • USB Type-C Cable and Connector Specification
Background data
composite
Background dataset
Modelled as a composite of its constituent materials.
Uncertainty
-30.6% / +38.9% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg

Outputs and waste

Wastewater Wastewaterm3 · ±25%
Derivation basis
  • Calculated from the water balance: fresh-water input minus evaporation.

No source is attached to this row.

Source citations
Not stated
Background data
carried, no background dataset
Background dataset
No treatment route recorded for this output.
Uncertainty
±25% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
m3
Rejected Assemblies Solid wastekg · -50.9% / +49.1%
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

No source is attached to this row.

Source citations
Not stated
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
-50.9% / +49.1% around the published quantity. The bounds themselves ship with the dataset on Circa.
Unit
kg
Silver Recovery Sludge Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

No source is attached to this row.

Source citations
Not stated
Background data
ecoinvent 3.12 treatment route
Background dataset
market for precious metal from electronics scrap, in anode slime
Uncertainty
No range defined.
Unit
g
FEP Scrap Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Niehoff Magazine EN. Double bow buncher, RBD line MSM 86 specific energy
  • Wire & Cable India Emagazine. Continuus-Properzi SAM machinery
  • HH-16 Multi wire Intermediate /fine wire drawing machine with annealing. Hooha HK
  • Niehoff 2017-2018 Cable Industry Guide. (MSM 86, R 502)
  • An Ultra-Fast Annealing Treatment by Electropulsing during Pure Copper Wire Drawing
  • Leading the way in sustainable lubrication. CONDAT Lubricants
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
No range defined.
Unit
g
Foil Trim Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Komax Alpha 530 / UniCrimp 208 Specifications, Komax Group, Published 2022
  • JacketStrip 8310 Technical Specifications, Symartech
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • HK-500 Triple Twisting Machine for CAT5/CAT6 Cable Manufacturing, HK Cable Machine
  • 48 Spindles Steel Wire Braiding Machine Specifications, Shenzhen Adp Communication Technology
  • 16 Spindle Braiding Machine Product Data, Srichand Engineering
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
No range defined.
Unit
g
Wire Scrap Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Komax Alpha 530 / UniCrimp 208 Specifications, Komax Group, Published 2022
  • JacketStrip 8310 Technical Specifications, Symartech
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • HK-500 Triple Twisting Machine for CAT5/CAT6 Cable Manufacturing, HK Cable Machine
  • 48 Spindles Steel Wire Braiding Machine Specifications, Shenzhen Adp Communication Technology
  • 16 Spindle Braiding Machine Product Data, Srichand Engineering
Background data
ecoinvent 3.12 treatment route
Background dataset
market for copper scrap, sorted, pressed
Uncertainty
No range defined.
Unit
g
TPE Scrap Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Niehoff Magazine EN. Double bow buncher, RBD line MSM 86 specific energy
  • Wire & Cable India Emagazine. Continuus-Properzi SAM machinery
  • HH-16 Multi wire Intermediate /fine wire drawing machine with annealing. Hooha HK
  • Niehoff 2017-2018 Cable Industry Guide. (MSM 86, R 502)
  • An Ultra-Fast Annealing Treatment by Electropulsing during Pure Copper Wire Drawing
  • Leading the way in sustainable lubrication. CONDAT Lubricants
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
No range defined.
Unit
g
Jacket Strip Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Komax Alpha 530 / UniCrimp 208 Specifications, Komax Group, Published 2022
  • JacketStrip 8310 Technical Specifications, Symartech
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • HK-500 Triple Twisting Machine for CAT5/CAT6 Cable Manufacturing, HK Cable Machine
  • 48 Spindles Steel Wire Braiding Machine Specifications, Shenzhen Adp Communication Technology
  • 16 Spindle Braiding Machine Product Data, Srichand Engineering
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
No range defined.
Unit
g
Conductor Trim Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Komax Alpha 530 / UniCrimp 208 Specifications, Komax Group, Published 2022
  • JacketStrip 8310 Technical Specifications, Symartech
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • HK-500 Triple Twisting Machine for CAT5/CAT6 Cable Manufacturing, HK Cable Machine
  • 48 Spindles Steel Wire Braiding Machine Specifications, Shenzhen Adp Communication Technology
  • 16 Spindle Braiding Machine Product Data, Srichand Engineering
Background data
ecoinvent 3.12 treatment route
Background dataset
market for copper scrap, sorted, pressed
Uncertainty
No range defined.
Unit
g
Label Backing Solid wasteg
Derivation basis
  • Calculated from the mass balance of spent materials and consumables, with treatment selected from the waste classification.

The sources below come from the manufacturing operations behind this row.

Sources (inherited)
Inherited, rolled up from the contributing process steps:
  • Komax Alpha 530 / UniCrimp 208 Specifications, Komax Group, Published 2022
  • JacketStrip 8310 Technical Specifications, Symartech
  • Model TZ-PT500 & TZ-PT630 Pair Twist + Back Twist Machine Specifications, TaiZheng Machine
  • HK-500 Triple Twisting Machine for CAT5/CAT6 Cable Manufacturing, HK Cable Machine
  • 48 Spindles Steel Wire Braiding Machine Specifications, Shenzhen Adp Communication Technology
  • 16 Spindle Braiding Machine Product Data, Srichand Engineering
Background data
ecoinvent 3.12 treatment route
Background dataset
treatment of inert waste, sanitary landfill
Uncertainty
No range defined.
Unit
g

Emissions to air

No emissions to air are recorded at this level.

Emissions to water

No emissions to water are recorded at this level.

Flows not quantified

3 flows are recorded for this dataset but carry no quantity — cut off below the significance threshold, or with no background dataset available. They remain inside the declared system boundary; each is listed with its reason.

Not modelled (3)

Process materials, cable fabrication steps Materialkg
Derivation basis
Not stated
Source citations
Not stated
Background data
not modelled
Background dataset
Not applicable: this flow is not quantified in the inventory.
Reason
The referenced fabrication steps consume process materials that are recorded but not quantified in this dataset; this cable model carries only the energy of those steps - deferred, not judged immaterial.
Uncertainty
No range defined.
Unit
kg
Process chemicals, cable fabrication steps Process chemicalkg
Derivation basis
Not stated
Source citations
Not stated
Background data
not modelled
Background dataset
Not applicable: this flow is not quantified in the inventory.
Reason
The referenced fabrication steps consume process chemicals that are recorded but not quantified in this dataset; this cable model carries only the energy of those steps - deferred, not judged immaterial.
Uncertainty
No range defined.
Unit
kg
Process water, cable fabrication steps WaterL
Derivation basis
Not stated
Source citations
Not stated
Background data
not modelled
Background dataset
Not applicable: this flow is not quantified in the inventory.
Reason
The referenced fabrication steps use process water that is recorded but not quantified in this dataset; this cable model carries only the energy of those steps - deferred, not judged immaterial.
Uncertainty
No range defined.
Unit
L

Limitations and unquantified flows (2)

Limits this dataset declares about itself: first any limit stated in its own description, then any limit it declares flow by flow, grouped by channel. Each entry below is the model's own disclosure.

  • Not quantifiedRinse-water effluent from the plating line is not quantified on this dataset, although the inventory books the recovery sludge that line produces.
  • These flows are named in this inventory but ship without a quantity, so their burden is not carried anywhere in the dataset: Process chemicals, cable fabrication steps; Process materials, cable fabrication steps; Process water, cable fabrication steps. Each row states its own reason on the row itself.

The flows above are this dataset's own records. What follows are the scope rules set once for the whole database in the methodology report, repeated here so every dataset page carries them.

Database-wide boundary policy — applies to every REEL dataset

These boundaries are set once for the whole database, in Chapter 2 of the methodology report, and apply to this dataset wherever they are relevant to it. The excluded flows listed above are specific to this dataset.

Use phase
Product operation is outside the cradle-to-gate scope.
End-of-life treatment
Recycling and disposal are outside the cradle-to-gate scope.
Distribution and retail
The gate is a finished component ready for integration into a higher-level assembly.
Inbound transport of raw materials
Transport of purchased raw materials to the manufacturing facility is already inside the upstream "market for" datasets that users link to a background database, so it is not modelled a second time here. This does not cover freight between REEL production stages, which is modelled where a dataset authors it.
Returnable shipping containers
Where freight between production stages is modelled, the mass moved is the product itself. The shipping container (FOSB, SEMI M31) is returnable capital equipment whose per-trip share is unsourced, so its tare is excluded from the transport effort.
Photomask fabrication
A mask set's embodied burden is amortised across a high-volume production run and is not attributed per wafer. Users assessing low-volume production should add mask fabrication separately; the methodology report gives the basis for the exclusion.
Employee transport, administration and R&D overhead
Employee transportation, facility administration and R&D/pilot-production overhead are outside scope.
Capital goods
Manufacturing equipment, cleanroom construction and facility infrastructure are excluded, on the grounds of absent public data on equipment embodied energy, uncertainty in equipment lifetime and allocation, common practice in electronics LCA, and a focus on the operational inventory. Future versions may include capital goods when sufficient public data becomes available.
Precious metal recovery credits
Scrap recovery credits for precious metals are excluded pending data availability.
Wafer reclaim
Test wafers and scrap are outside the system boundary.

Inside the boundary, linked rather than modelled

Silicon ingot growth and wafer slicing
Inside the cradle-to-gate scope, but treated as upstream material inputs linked to background databases rather than modelled as REEL processes.
Freight between production stages
Where a dataset's product moves between REEL production stages - wafer fabrication to the packaging site, for example - that leg is authored as a transport service and linked to an ecoinvent freight activity. It is measured as a transport effort in tonne-kilometres, not as a mass. Route distances are authored per route class with a stated band; a lower bound of zero is a modelling statement that the two sites can be co-located, not a missing value.

Cut-off criteria

A flow is excluded from a process inventory when it contributes less than 1 % of the total mass of inputs to that unit process, or less than 1 % of its total energy input. The denominator is total process inputs, not product mass. That distinction matters in semiconductor manufacturing, where the input mass of water, chemicals and gases greatly exceeds the product mass, so the threshold removes only genuinely minor flows.

Included regardless of the cut-off

  • Perfluorocarbons (CF4, C2F6, SF6, NF3) - high GWP, EPA regulated
  • Heavy metals (Pb, Cd, Hg, Cr(VI)) - RoHS regulated, high toxicity
  • Volatile organics (photoresist solvents, PGMEA) - air quality
  • Precious metals (Au, Ag, Pd, Pt) - high embodied impacts
  • Ozone-depleting substances (legacy CFCs, HCFCs) - Montreal Protocol