Float glass and surface ground or polished glass, in sheets

1. Scope and Applicability

This PCR supports foreground data packages for continuous flat-glass manufacture through delivery of unworked sheets at the factory gate. It covers ordinary clear, low-iron, body-tinted or opacified float glass and, where declared, sheets whose faces are surface ground or polished. An online coating made during the hot ribbon process may be included only as a declared conditional unit process and qualifier.

The data package shall identify the glass kind, applicable ground or polished state, nominal and measured thickness, sheet area and mass, iron content or an applicable light-transmittance specification, online-coating status, total and source-separated cullet content, furnace technology and energy carriers, tin-bath forming, annealing, edge-trim/cutting yield, and the delivered sheet state. Product-specific optical or iron values must come from test records or specifications; this PCR sets no generic performance threshold.

The category does not include tempered or heat-strengthened safety glass, laminated glass, insulating glass units, mirrors, offline or downstream coating, fabrication beyond cutting to unworked sheet dimensions, or an exclusively photovoltaic-cover-glass product class. Such downstream operations require separate unit processes or a more specific PCR and must not be extrapolated to this category.

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.other-transportable-goods-except-metal-products-machinery-and-equipment.glass-and-glass-products-and-other-non-metallic-products-n-e-c.float-glass-and-surface-ground-or-polished-glass-in-sheets
classification_refs	CPC 3.0 37113, exact
covered_products	Unworked sheets of float glass and surface-ground or polished glass; ordinary clear, low-iron, body-tinted or opacified variants; online-coated ribbon only when declared
excluded_products	Cast, rolled, drawn or blown sheet glass classified elsewhere; worked sheet glass; tempered or laminated safety glass; insulating glass units; mirrors; offline/downstream-coated or fabricated glazing products
representative_product	Declared mass of saleable, quality-accepted sheet glass at the factory gate
production_route	Batch preparation, melting/refining, float forming on molten tin, annealing, conditional surface grinding/polishing or online coating, inspection, cutting, cullet return and packing
market_state	Unworked sheets, jumbo sheets or cut-to-size stock sheets as delivered; dimensions and packing state declared

3. Reference Flow

Field	Value
What	Saleable float glass or applicable surface-ground/polished glass sheets matching the declared kind and delivery state
How much	1,000 kg net accepted product at the declared factory gate
How well	Glass kind, processing state, thickness, dimensions, density basis, iron content or optical specification, coating status, cullet statement and quality-acceptance basis declared
How long or cycle	One reporting period representative of continuous production, normally at least 12 consecutive months
reference_flow_link	Tiangong process identity candidate d6c1bf92-3556-448b-92d3-b8485d4c8e89; identity only, with no inventory values inherited

Field	Value
Reference amount	1,000 kg
Reference product flow	Float glass and surface ground or polished glass, in sheets 1b43024e-16ea-42d2-830d-329c4a2abc3d
Reference flow property	Mass 93a60a56-a3c8-11da-a746-0800200b9a66
Reference unit group	Units of mass 93a60a57-a4c8-11da-a746-0800200b9a66
Reference unit	kg
Required qualifiers	glass kind: ordinary clear, low-iron, tinted or opacified; float or surface-ground/polished state; nominal and measured thickness; accepted area and net mass; measured density or declared conversion basis; iron content or applicable light-transmittance specification and test method; online coating present/absent and chemistry/function when present; internal, pre-consumer external and post-consumer cullet fractions; furnace type and fuel/electricity carriers; tin-bath and annealing route; cutting yield; delivered sheet dimensions and packing state; geography; reporting period; factory gate

When constructing a foreground data package, the items listed in Required qualifiers must be declared in dataset metadata, process notes, reference flow comment, product description, or an equivalent data package field. Missing required qualifiers make the reference flow definition incomplete for that data package.

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_product_mass	net accepted reference product	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Normalize every exchange to 1,000 kg of saleable, quality-accepted sheets after edge trimming and rejection; exclude packing mass.
area_mass_conversion	conversion between area and mass	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Use mass = accepted area × measured mean thickness × measured product density. If measured density is unavailable for soda-lime-silicate glass, 2,500 kg/m3 may be used only as the EN 572-1 conventional calculation value and must be disclosed; do not use it for a different composition without evidence.
thickness_area_records	each saleable product group	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Record accepted area and thickness distribution by product group; do not convert a mixed-thickness output using one undeclared nominal thickness.
cullet_fraction	batch cullet statement	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg/kg batch	Calculate internal, pre-consumer external and post-consumer cullet separately on a dry batch-input mass basis; report their sum and do not count internally returned edge trim as external recycled content.
cutting_yield	inspection and cutting	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg/kg ribbon input	Cutting yield equals net accepted unpacked sheet mass divided by annealed ribbon mass entering inspection/cutting for the same reporting boundary.
optical_iron_declaration	product identity and performance qualifier	declared test property	declared method unit	Declare either measured total iron/iron-oxide content or an applicable light-transmittance specification and test method. Low-iron, tinted and coated variants shall not inherit ordinary-clear performance.

5. System Boundary

rule_id	Applies to	Rule	source_ids
boundary_inputs	cradle-to-gate foreground data package	Include receiving and preparation of virgin batch materials, separately identified cullet, fuels, electricity, water, process gases, tin make-up, coating or polishing materials when applicable, and packaging.	nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013
boundary_core	required manufacturing	Include batching, melting/refining, float forming on molten tin, annealing, inspection, edge trimming, cutting, internal cullet return, quality rejection and packing.	eu-jrc-glass-bref-2013; eurofloat-epd-2024; vitro-flat-glass-epd-2024
boundary_conditionals	route-specific manufacturing	Include online coating and surface grinding/polishing only when performed before the declared gate; record them as separate conditional processes.	unsd-hs-7005; eu-jrc-glass-bref-2013
boundary_gate	delivery state	End at the factory gate with quality-accepted, unworked sheets in the declared jumbo or cut stock-sheet and packing state.	nga-flat-glass-pcr-2020; eurofloat-epd-2024
boundary_exclusions	downstream products and use/end-of-life	Exclude tempering, heat strengthening, laminating, insulating-unit assembly, silvering/mirror manufacture, offline/downstream coating, installation, use and end-of-life; model any brought-in operation separately and do not relabel it as category-wide float-glass production.	unsd-cpc-3-0-explanatory-notes-2025; unsd-hs-7005; nga-flat-glass-pcr-2020
boundary_cutoff	omitted flows	Seek complete mass and energy balance. Any cutoff shall be disclosed and justified; a flow expected to be environmentally relevant shall be included regardless of mass.	nga-flat-glass-pcr-2020

Boundary Abstraction

Field	Value
declared_starting_condition	batch_materials_and_cullet_received_at_float_glass_site
starting_condition_role	purchased_or_transferred_inputs_to_continuous_flat_glass_manufacture
product_classification_scope	CPC 3.0 37113, unworked float or surface-ground/polished glass in sheets
recursive_input_rule	same-category glass input shall remain visible as purchased or transferred cullet/sheet input and shall not be silently absorbed into the reference output
upstream_dataset_requirement	link purchased materials, fuels, electricity, water, gases and packaging to geographically and technologically appropriate upstream datasets
disclosure	identify product mix, glass kind, thickness mix, coating/polishing route, cullet origin, furnace and energy carriers, site(s), period, gate and included packaging

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
batch_preparation	Batch material and cullet preparation	required		foreground	prepared batch delivered to melting
melting_refining	Furnace melting and refining	required		foreground	molten glass delivered to forming
float_forming	Tin-bath float forming	required		foreground	glass ribbon leaving the tin bath
annealing	Annealing lehr	required		foreground	annealed ribbon entering inspection
surface_finishing	Surface grinding or polishing	conditional	include only for a declared surface-ground or polished product	foreground	finished ribbon delivered to inspection/cutting
online_coating	Online hot-ribbon coating	conditional	include only when an online coating is present within the declared gate	foreground	online-coated ribbon
inspection_cutting_packing	Inspection, edge trimming, cutting and packing	required		foreground	1,000 kg accepted unpacked sheet product

Process: Batch material and cullet preparation (batch_preparation)

Inputs

Product flows

Virgin batch materials (virgin_batch_materials)

Record silica sand, soda ash, limestone, dolomite and every minor batch constituent as separate site-selected product flows; preserve composition and moisture records rather than using an undeclared generic batch.

• Selected flow: Site-selected virgin glass batch material flows, one row per material in the produced dataset
• Flow property / unit: Mass / kg
• Amount rule: dry mass charged by constituent
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg net accepted sheet product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_batch_materials
• Sources: eu-jrc-glass-bref-2013

Internal and external cullet (cullet_inputs)

Record internal return cullet, pre-consumer external cullet and post-consumer cullet as distinct inputs. Supplier or site classification evidence is required for external fractions.

• Selected flow: Site-selected glass cullet product flows separated by origin
• Flow property / unit: Mass / kg
• Amount rule: dry charged mass by cullet origin
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per kg total dry batch input and per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_cullet_inputs
• Sources: nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013
• Range: sector screening range for total cullet charged, not a default or conformance threshold
  • Range role: QA guardrail (qa_guardrail)
  • Lower: 0.10
  • Upper: 0.40
  • Unit: kg/kg total batch input
  • Basis: total cullet charged to a float furnace divided by total batch input
  • Basis kind: Process output (process_output)
  • Evidence kind: External source (external_source)
  • Sources: eu-jrc-glass-bref-2013

Outputs

Product flows

Prepared batch (prepared_batch)

The mixed batch output carries the measured constituent and cullet masses to the melting process.

• Selected flow: Prepared flat-glass batch
• Flow property / unit: Mass / kg
• Amount rule: calculated from charged constituents, retained moisture corrections and preparation losses
• Value mode: Calculated value (calculated_value)
• Specificity: Site-specific (site_specific)
• Normalization basis: batch transferred to melting per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_batch_materials
• Sources:

Process: Furnace melting and refining (melting_refining)

Inputs

Product flows

Furnace fuels (furnace_fuels)

Record each fuel by lower heating value and physical quantity; identify oxy-fuel, air-fuel, electric-boost or other furnace configuration.

• Selected flow: Site-selected natural gas, fuel oil or other furnace fuel flows
• Flow property / unit: Energy / MJ lower heating value, with physical units retained
• Amount rule: metered fuel consumption by carrier
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per tonne molten glass and per 1,000 kg reference product
• Basis kind: Fuel inventory (fuel_inventory)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_energy_carriers
• Sources: eu-jrc-glass-bref-2013
• Range: European sector screening range for melting energy across carriers, not fuel-only and not a default
  • Range role: QA guardrail (qa_guardrail)
  • Lower: 5.2
  • Upper: 8.7
  • Unit: GJ/t molten glass
  • Basis: total melting energy input reported for furnace melting
  • Basis kind: Process output (process_output)
  • Evidence kind: External source (external_source)
  • Sources: eu-jrc-glass-bref-2013

Purchased electricity (melting_electricity)

Record metered electricity separately from fuels, including electric boosting and furnace auxiliaries assigned to this process; use the supplier or residual/grid mix required by the study framework.

• Selected flow: Site- and market-appropriate electricity supply flow
• Flow property / unit: Energy / kWh
• Amount rule: metered electricity assigned to melting and refining
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per tonne molten glass and per 1,000 kg reference product
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_energy_carriers
• Sources: nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013

Outputs

Product flows

Molten refined glass (molten_refined_glass)

Record molten glass transferred to the tin bath from furnace production and mass-balance records.

• Selected flow: Molten refined flat glass
• Flow property / unit: Mass / kg
• Amount rule: calculated mass transferred from furnace to forming
• Value mode: Calculated value (calculated_value)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_furnace_mass_balance
• Sources:

Elementary flows

Direct furnace emissions (direct_furnace_emissions)

Record carbon dioxide from fuel and carbonate decomposition and monitored nitrogen oxides, sulfur oxides, particulate matter and other permit-relevant releases as separate elementary flows.

• Selected flow: Site-selected elementary flow for each emitted substance and compartment
• Flow property / unit: Mass / kg
• Amount rule: monitored or calculated annual emission by substance, with method identified
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_direct_emissions
• Sources: eu-jrc-glass-bref-2013

Process: Tin-bath float forming (float_forming)

Inputs

Product flows

Tin-bath gases and tin make-up (tin_bath_operating_inputs)

Record nitrogen, hydrogen, sulfur dioxide and tin make-up actually used to maintain the bath atmosphere and equipment; do not assume these inputs are zero.

• Selected flow: Site-selected tin, nitrogen, hydrogen and sulfur-dioxide supply flows, one row per material in the produced dataset
• Flow property / unit: Mass / kg or gas volume converted with declared conditions
• Amount rule: metered, purchased or inventory-adjusted use
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per tonne ribbon leaving the tin bath and per 1,000 kg reference product
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_process_materials
• Sources: eu-jrc-glass-bref-2013

Outputs

Product flows

Float glass ribbon (float_glass_ribbon)

The ribbon output records actual mass and thickness distribution after float forming.

• Selected flow: Float glass ribbon
• Flow property / unit: Mass / kg
• Amount rule: calculated or measured ribbon mass transferred to the lehr
• Value mode: Calculated value (calculated_value)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_ribbon_output
• Sources:

Process: Annealing lehr (annealing)

Inputs

Product flows

Lehr fuel and electricity (annealing_energy)

Record lehr fuel and electricity separately by carrier using meters or a documented allocation from shared utilities.

• Selected flow: Site-selected lehr fuel and electricity supply flows
• Flow property / unit: Energy / MJ and kWh
• Amount rule: metered or documented shared-utility assignment by carrier
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per tonne annealed ribbon and per 1,000 kg reference product
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_energy_carriers
• Sources: eu-jrc-glass-bref-2013

Outputs

Product flows

Annealed ribbon (annealed_ribbon)

Record the ribbon mass entering finishing or inspection and retain thickness/product group linkage.

• Selected flow: Annealed flat-glass ribbon
• Flow property / unit: Mass / kg
• Amount rule: calculated or measured mass leaving the lehr
• Value mode: Calculated value (calculated_value)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_ribbon_output
• Sources:

Process: Surface grinding or polishing (surface_finishing)

Inputs

Product flows

Surface-finishing materials and utilities (surface_finishing_inputs)

When this route applies, record abrasives, water, electricity and other consumables separately and declare the treated surface and removed thickness.

• Selected flow: Site-selected abrasive, water and electricity flows
• Flow property / unit: Mass / kg, water / m3 and energy / kWh
• Amount rule: measured consumption attributable to surface grinding or polishing
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg surface-finished output
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_conditional_process_inputs
• Sources: unsd-cpc-3-0-explanatory-notes-2025

Outputs

Product flows

Surface-finished ribbon (surface_finished_ribbon)

Record accepted ground or polished glass mass and route it to inspection/cutting; declare whether one or both faces were treated.

• Selected flow: Surface-ground or polished glass ribbon
• Flow property / unit: Mass / kg
• Amount rule: measured accepted output mass
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg surface-finished reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_conditional_process_outputs
• Sources:

Process: Online hot-ribbon coating (online_coating)

Inputs

Product flows

Online coating precursors and utilities (online_coating_inputs)

When an online coating is present, record precursor chemistry, carrier gases and energy within this process. Offline or later coating is outside this PCR boundary.

• Selected flow: Site-selected coating precursor, carrier-gas and utility flows
• Flow property / unit: Mass / kg and energy / kWh or MJ
• Amount rule: metered or reconciled consumption for online coating
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg online-coated output
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_conditional_process_inputs
• Sources: unsd-hs-7005; eu-jrc-glass-bref-2013

Outputs

Product flows

Online-coated ribbon (online_coated_ribbon)

Record coated ribbon mass and declare coating chemistry/function, coated face and quality acceptance; do not apply it to uncoated production.

• Selected flow: Online-coated float glass ribbon
• Flow property / unit: Mass / kg
• Amount rule: measured accepted output mass
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg online-coated reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_conditional_process_outputs
• Sources:

Process: Inspection, edge trimming, cutting and packing (inspection_cutting_packing)

Inputs

Product flows

Packaging materials and finishing electricity (packing_and_cutting_inputs)

Record electricity for inspection/cutting and each packaging material. Packaging remains an input but is excluded from net reference-product mass.

• Selected flow: Site-selected electricity and packaging material flows, one row per input in the produced dataset
• Flow property / unit: Energy / kWh and mass / kg
• Amount rule: metered electricity and purchased/issued packaging mass
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_cutting_packing_inputs
• Sources: nga-flat-glass-pcr-2020; eurofloat-epd-2024

Outputs

Product flows

Accepted sheet glass (accepted_sheet_glass)

This is the reference product output after inspection and cutting, before including packaging mass.

• Selected flow: Float glass and surface ground or polished glass, in sheets 1b43024e-16ea-42d2-830d-329c4a2abc3d
• Flow property / unit: Mass / kg
• Amount rule: sum accepted sheet masses at the declared dimensions and thicknesses; normalize to 1,000 kg
• Value mode: Calculated value (calculated_value)
• Specificity: Product-specific (product_specific)
• Normalization basis: 1,000 kg net accepted unpacked sheet product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_accepted_sheet_output
• Sources:

Waste flows

Edge trim, rejects and breakage (cutting_cullet_and_rejects)

Measure edge trim, offcuts, quality rejects and breakage. Record the internal-remelt fraction separately from cullet transferred outside the site and final waste treatment.

• Selected flow: Site-selected glass cullet or waste flow by destination
• Flow property / unit: Mass / kg
• Amount rule: measured mass by cause and destination
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per kg ribbon entering inspection/cutting and per 1,000 kg reference product
• Basis kind: Process output (process_output)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_cutting_yield
• Sources: nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013
• Range: provisional broad cutting-yield screen, replace with reviewed product/site evidence
  • Range role: QA guardrail (qa_guardrail)
  • Lower: 0.80
  • Upper: 1.00
  • Unit: kg accepted sheet/kg annealed ribbon input
  • Basis: net accepted unpacked sheets divided by ribbon entering inspection/cutting
  • Basis kind: Process output (process_output)
  • Evidence kind: Reasoned estimate (reasoned_estimate)
  • Sources:

7. Allocation and Co-product Handling

rule_id	Applies to	Rule	source_ids
allocation_avoid	product groups, lines and conditional processes	First avoid allocation through meter separation, production-line or campaign subdivision, and separate modelling of online coating or surface finishing.	nga-flat-glass-pcr-2020
allocation_recycled_glass	internal and external cullet	Internal edge trim and rejects returned within the site carry forward the burdens already inside the system and receive no recycled-content credit. External cullet shall use the recycled-material convention required by the declared study framework, with origin and any collection/processing burdens disclosed.	nga-flat-glass-pcr-2020
allocation_shared_energy	shared furnace, utilities and lehr	After subdivision is exhausted, allocate shared mass/energy-driven burdens by a documented physical relationship such as mass, energy demand or operating time that reflects causality.	nga-flat-glass-pcr-2020
allocation_coproducts	saleable co-products	If a co-product with material economic value remains and physical causality cannot be established, use economic allocation with contemporaneous prices and disclose a sensitivity result.	nga-flat-glass-pcr-2020
allocation_no_avoided_burden	exported cullet, heat or by-products	Do not subtract an avoided burden inside the core product inventory unless the declared LCA framework explicitly requires system expansion; report exports and method separately.	nga-flat-glass-pcr-2020

8. Foreground Data Collection, Calculation, and Quality Rules

Data Collection Protocols

protocol_id	process_id	flow_role	record_type	raw_fields	collection_method	unit	frequency	temporal_coverage	site_scope	aggregation_rule	quality_evidence
cp_batch_materials	batch_preparation	virgin batch materials and prepared batch	batch ticket and stock reconciliation	material id; supplier; wet mass; moisture; dry mass; formulation; batch id	calibrated scale plus stock reconciliation	kg dry	per batch and monthly reconciliation	representative reporting period, normally 12 months	each included float line/site	sum dry constituent masses and normalize to accepted output	scale calibration; batch tickets; purchase/stock records
cp_cullet_inputs	batch_preparation	internal and external cullet	cullet charge and origin record	mass; internal/external; pre/post-consumer; contamination; supplier; batch	calibrated scale and origin documentation	kg dry	per charge or lot	same period as output	each included site	sum by origin; calculate fractions on total dry batch input	scale calibration; supplier declarations; internal return log
cp_energy_carriers	melting_refining; annealing	fuel and electricity	meter, invoice and lower-heating-value record	carrier; physical quantity; energy; meter id; process assignment; supplier/grid mix	calibrated meter; invoice reconciliation; documented shared-meter allocation	MJ LHV; kWh	continuous/monthly	same period as output	each furnace and included utilities	sum by carrier and allocate only after subdivision	meter calibration; invoices; allocation worksheet
cp_furnace_mass_balance	melting_refining	molten refined glass	furnace production balance	batch input; cullet; volatilization estimate; pull rate; transferred mass; period	production controls reconciled to mass inputs and outputs	kg	shift/daily, monthly reconciliation	same period as output	each furnace	reconcile furnace pull to downstream ribbon and losses	control-system export; signed reconciliation
cp_direct_emissions	melting_refining	direct furnace emissions	stack monitoring and calculation record	substance; compartment; concentration; gas flow; fuel/carbonate input; method; uncertainty	continuous/periodic monitoring or documented mass/emission calculation	kg	permit frequency, aggregated monthly	same period as output	each included stack	calculate by substance and normalize to accepted output	monitoring QA/QC; laboratory report; calculation file
cp_process_materials	float_forming	tin-bath operating inputs	meter and stock record	material; purchase; opening/closing stock; replenishment; gas conditions	meter or inventory reconciliation	kg; Nm3 with conditions	continuous/monthly	same period as output	each tin bath	convert gas volume with declared conditions and sum by flow	meter calibration; inventory reconciliation
cp_ribbon_output	float_forming; annealing	ribbon output	line production record	timestamp; width; length; thickness; density basis; mass; product group	line sensors reconciled with weighbridge/product records	m2; mm; kg	continuous	same period as output	each included line	calculate mass by group and reconcile to accepted output plus cullet	sensor calibration; production reports
cp_conditional_process_inputs	surface_finishing; online_coating	conditional process inputs	meter, recipe and issue record	product group; material; chemistry; quantity; meter; treated area/mass	process meter and material issue reconciliation	kg; m3; kWh; MJ	per campaign/monthly	same period as conditional output	each applicable process	sum only for products receiving the operation	recipes; meter calibration; issue records
cp_conditional_process_outputs	surface_finishing; online_coating	conditional process output	production and quality record	input mass; accepted output; rejects; treated face; removed thickness or coating specification	production system and quality inspection	kg; m2; mm	per lot/campaign	same period as output	each applicable process	sum accepted output by declared treatment	inspection/test reports; production records
cp_cutting_packing_inputs	inspection_cutting_packing	cutting electricity and packaging	meter and material issue record	electricity; material id; issue mass; returned stock; product group	submeter or documented allocation plus stock reconciliation	kWh; kg	monthly	same period as output	each cutting/packing area	sum by input and normalize to accepted output	meter data; purchase/stock reconciliation
cp_cutting_yield	inspection_cutting_packing	edge trim, rejects and breakage	cutting and rejection log	ribbon input mass; accepted mass; edge trim; reject reason; breakage; internal return; external destination	line mass/area records and calibrated scales	kg	shift/lot, monthly reconciliation	same period as output	each included line	yield = accepted mass / ribbon input; reconcile every residual by destination	scale/sensor calibration; rejection and transfer records
cp_accepted_sheet_output	inspection_cutting_packing	accepted reference product	shipment, packing and quality record	product group; glass kind; state; thickness; dimensions; area; net mass; packing mass; coating; optical/iron result	calibrated scale or validated area-thickness-density calculation linked to acceptance	kg; m2; mm	per pack/lot	same period as inputs	each included cutting and packing area	sum net accepted mass by product group; exclude packing mass	calibration; calculation check; test certificate; shipment record

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
calc_area_mass	sheet mass from geometry	mass_kg = accepted_area_m2 × mean_thickness_m × density_kg_per_m3; retain unrounded intermediate values	cp_ribbon_output; cp_accepted_sheet_output	kg sheet glass	en-572-1-2012
calc_cullet_fraction	cullet content	cullet fraction by origin = dry cullet mass by origin / total dry batch-input mass; total cullet is the sum of origin fractions	cp_batch_materials; cp_cullet_inputs	kg/kg dry batch input	nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013
calc_cutting_yield	inspection/cutting yield	cutting yield = net accepted unpacked sheet mass / annealed ribbon mass entering inspection/cutting	cp_ribbon_output; cp_cutting_yield; cp_accepted_sheet_output	kg/kg ribbon input
calc_reference_normalization	all inventory exchanges	normalized exchange = reporting-period exchange × 1,000 kg / reporting-period net accepted reference-product mass	all applicable collection protocols	exchange per 1,000 kg reference product
calc_mass_balance	each process and full foreground system	input mass = product output + internally transferred cullet + exported waste + releases + documented stock change; explain non-measured residuals	batch, furnace, ribbon, cutting and output records	reconciled mass balance and residual	eu-jrc-glass-bref-2013

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
dq_representativeness	foreground period and product mix	Use a period representative of stable continuous operation, normally at least 12 consecutive months; disclose shutdowns, rebuilds, abnormal campaigns and product-mix weighting.	dated production and operating records
dq_primary_data	controlled foreground processes	Use primary site data for all included operations under operational control and report coverage by mass and energy.	meters, batch records, production records and coverage calculation
dq_identity	each declared product group	Link ordinary/low-iron/tinted state, ground/polished state, coating status, thickness, dimensions and optical/iron evidence to the output group.	specification, test certificate and production master data
dq_energy	furnace, lehr and auxiliaries	Keep fuels and electricity separate, state heating-value basis, electricity mix and shared-meter allocation; do not infer a fuel/electricity split from sector totals.	meter/invoice reconciliation and allocation worksheet
dq_mass_balance	batch through saleable sheet	Reconcile dry batch, cullet, molten/ribbon transfers, accepted output, internal returns, exported waste, emissions and stock change; investigate material residuals.	signed mass-balance worksheet
dq_secondary_data	upstream datasets	Select temporally, geographically and technologically representative datasets and document substitutions and data age.	dataset register and data-quality assessment
dq_reasoned_estimate	provisional cutting-yield QA range	Treat the 0.80–1.00 range only as a replaceable author screening value; it is neither a default inventory value nor a performance, legal or conformance threshold.	explicit estimate label and replacement review

9. Validation Rules

rule_id	Applies to	Rule	source_ids
validate_identity	reference product	The product resolves to CPC 3.0 37113 and declares glass kind, applicable surface state, thickness, dimensions, delivery state and online-coating status.	unsd-cpc-3-0-explanatory-notes-2025; unsd-hs-7005
validate_reference_flow	reference flow	Net accepted unpacked output equals 1,000 kg and uses product flow 1b43024e-16ea-42d2-830d-329c4a2abc3d, Mass property 93a60a56-a3c8-11da-a746-0800200b9a66, Units of mass group 93a60a57-a4c8-11da-a746-0800200b9a66, and kg.
validate_area_mass	geometry conversion	Every area-to-mass conversion identifies area, thickness and density; use of 2,500 kg/m3 is limited to the disclosed EN 572-1 conventional soda-lime-silicate calculation value.	en-572-1-2012
validate_optical_iron	product qualifier	Iron content or applicable light-transmittance evidence is product-group specific and identifies the test/specification method; no category-wide value is inferred.	en-572-1-2012
validate_cullet	cullet statement	Internal, pre-consumer external and post-consumer cullet masses and fractions are separately reported and reconcile to total dry batch input.	nga-flat-glass-pcr-2020; eu-jrc-glass-bref-2013
validate_processes	process map	Melting/fuels/electricity, tin bath, annealing and inspection/cutting are present; surface finishing and online coating are included only when applicable and remain separately visible.	eu-jrc-glass-bref-2013
validate_yield	cutting and mass balance	Ribbon input, accepted output, internal return, external waste and stock change reconcile, and cutting yield is reported; a value outside the reasoned-estimate screen triggers review but not automatic nonconformance.
validate_exclusions	scope protection	Tempering, laminating, insulating-unit assembly, mirrors, offline coating and downstream fabrication are excluded or modelled as explicitly separate downstream processes; photovoltaic cover glass is not generalized to the whole category.	unsd-hs-7005; nga-flat-glass-pcr-2020
validate_sources	evidence and estimates	Every source ID resolves in the data-source register, site measurements retain quality evidence, and any reasoned estimate is labelled provisional and replaceable.

10. Published Dataset Profile

Field	Value
dataset_role	foreground_unit_process_or_aggregated_cradle_to_gate_process
downstream_use	upstream material dataset for photovoltaic-module cover-glass, building-envelope and automotive-glazing studies when the declared product qualifiers match
allowed_use	unworked CPC 37113 sheet glass matching glass kind, thickness, optical/iron specification, online-coating status, geography, technology, period and factory gate
excluded_use	direct representation of tempered, laminated, insulating, mirrored, offline-coated, fabricated or single-purpose photovoltaic glass without additional specific processes and evidence
required_metadata	reference UUIDs; CPC code; glass kind; surface state; thickness/area/mass basis; density basis; iron or optical specification; online coating; cullet origin fractions; furnace and energy carriers; tin bath; annealing; cutting yield; delivery and packing state; geography; period; allocation; boundary
required_quality_disclosure	primary-data coverage; meter/calibration evidence; mass and energy reconciliation; product-mix weighting; upstream dataset choices; cutoff; allocation; estimate replacements; data-quality assessment
update_trigger	furnace rebuild or fuel switch; material electricity mix change; formulation or cullet-source change; coating/polishing route change; product-mix or thickness shift; boundary/allocation change; reporting data older than the declared validity period

11. Data Sources

Source id	Type	Reference	Used for
unsd-cpc-3-0-explanatory-notes-2025	official_guidance	United Nations Statistics Division, CPC Version 3.0 explanatory notes, 30 June 2025, https://unstats.un.org/unsd/classifications/Econ/Download/In%20Text/CPC_Ver_3.0_Exp_Notes_30Jun2025.pdf (accessed 2026-08-08)	authoritative CPC 37113 identity and separation from adjacent glass-product subclasses
unsd-hs-7005	official_guidance	United Nations Statistics Division, HS 2017 heading 7005 detail, https://unstats.un.org/unsd/classifications/Econ/Detail/EN/2089/7005 (accessed 2026-08-08)	unworked sheet scope and conditional absorbent, reflecting or non-reflecting layer context
nga-flat-glass-pcr-2020	standard	National Glass Association and NSF International, Product Category Rule for Environmental Product Declarations: NGA PCR for Flat Glass, Version 2.0, September 2020, https://www.glass.org/sites/default/files/2021-10/pcr_flat_glass_2020.pdf (accessed 2026-08-08; expired 2025-09-30)	historical category method evidence for declared mass, boundary, cutoff, allocation, cullet and primary-data rules; not asserted as current conformity authority
environdec-cpcr-009-flat-glass	official_guidance	International EPD System, c-PCR-009 Flat glass products, valid through 2030-04-07, https://www.environdec.com/pcr-library/pcr2019-14-c-pcr-009 (accessed 2026-08-08)	current flat-glass PCR landscape and need to use a more specific applicable program rule for an EPD claim
eu-jrc-glass-bref-2013	official_guidance	European Commission JRC/EIPPCB, Best Available Techniques Reference Document for the Manufacture of Glass, 2013, https://op.europa.eu/en/publication-detail/-/publication/ff8a3955-d0d0-46f5-8a15-4b638896cb56 (accessed 2026-08-08)	float-process decomposition, materials, cullet, energy, emissions, tin bath, annealing and sector QA ranges
en-572-1-2012	standard	EN 572-1:2012, Glass in building — Basic soda lime silicate glass products — Part 1: Definitions and general physical and mechanical properties, public preview https://cdn.standards.iteh.ai/samples/37400/fe7c33b74a5747198946b44e88108b42/SIST-EN-572-1-2012.pdf (accessed 2026-08-08)	float-glass definition, conventional 2,500 kg/m3 calculation density and optical-property test context
eurofloat-epd-2024	dataset	Glas Trösch / IBU, Environmental Product Declaration: Float glass in construction EUROFLOAT, 2024, https://www.euroglas.com/fileadmin/user_upload/Service/Nachweise_und_Zertifikate/Umwelt_und_Qualitaetszertifikate/Float_glass_in_construction_EUROFLOAT.pdf (accessed 2026-08-08)	manufacturer-specific corroboration of batch–furnace–tin bath–lehr–inspection/cutting route and delivery states; no category-wide default values
vitro-flat-glass-epd-2024	dataset	Vitro Architectural Glass, Environmental Product Declaration: Flat Glass Products, 2024, https://www.vitroglazings.com/media/nf0nm25r/vitro-epd-flat-glass-products.pdf (accessed 2026-08-08)	manufacturer-specific corroboration of clear, low-iron and tinted variants and process sequence; no category-wide default values