Flat-rolled products of non-alloy steel, not further worked than hot-rolled, of a width of less than 600 mm

1. Scope and Applicability

This PCR covers non-alloy-steel flat-rolled products whose finished width is less than 600 mm and whose metallurgical state is not further worked than hot-rolled. It covers narrow hot-rolled strip supplied in coils and hot-rolled flat products supplied in cut lengths. The production route may roll semi-finished steel directly to the declared width or may finish a wider hot-rolled non-alloy-steel product by trimming, slitting, or cutting without cold reduction or a change in metallurgical state. The foreground data package shall declare which route and which included unit processes produced the reference product.

Cold-rolled products; clad, plated, coated, pickled-and-oiled, polished, or otherwise surface-treated products; alloy and stainless steels; electrical steels; long products; tubes; and products with a finished width of 600 mm or more are excluded. Packaging, outbound transport beyond the mill gate, fabrication into a downstream article, use, and end of life are outside this PCR unless a study explicitly adds and reports them as separate downstream modules.

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.metal-products-machinery-and-equipment.basic-metals.flat-rolled-products-of-non-alloy-steel-not-further-worked-than-hot-rolled-of-a-width-o-85e134a9
classification_refs	CPC 3.0: 41212, exact product-classification context (un-cpc-3-0-structure-2025)
covered_products	Non-alloy-steel flat-rolled strip, coil, sheet, or cut length; finished width < 600 mm; not further worked than hot-rolled
excluded_products	Width >= 600 mm; alloy, stainless, or electrical steel; cold-reduced, clad, plated, coated, pickled-and-oiled, polished, or otherwise further-worked product; long product or tube
representative_product	Narrow hot-rolled non-alloy-steel strip coil at the producing or finishing mill gate
production_route	Declared direct hot-rolling route from semi-finished steel, or declared trimming/slitting/cutting route from a wider hot-rolled non-alloy-steel input without cold reduction or surface treatment
market_state	As-shipped dry coil, strip, sheet, or cut length; uncoated and without packaging mass in the reference amount

3. Reference Flow

Field	Value
What	Conforming flat-rolled non-alloy-steel product, finished width < 600 mm, not further worked than hot-rolled
How much	1,000 kg net conforming product, excluding packaging
How well	Declared steel grade, thickness, width, dimensional tolerance, edge condition, surface condition, and coil or cut-length form; no cold reduction, cladding, plating, coating, pickling-and-oiling, polishing, or other excluded further work
How long or cycle	No use cycle; production represented over a declared representative accounting period
reference_flow_link	reference_product_narrow_hot_rolled_non_alloy_steel

Field	Value
Reference amount	1,000 kg
Reference product flow	Flat-rolled products of non-alloy steel, not further worked than hot-rolled, of a width of less than 600 mm 9705bbad-51bd-4ee8-af46-21324f57c577
Reference flow property	Mass 93a60a56-a3c8-11da-a746-0800200b9a66
Reference unit group	Units of mass 93a60a57-a4c8-11da-a746-0800200c9a66
Reference unit	kg
Required qualifiers	non-alloy steel grade; finished width and thickness; dimensional tolerance; coil, strip, sheet, or cut-length form; edge and surface condition; direct-rolling or wider-strip finishing route; reheating furnace and rolling-mill configuration when applicable; fuel mix; electricity supplier or grid geography; water-circuit boundary; site and geography; production period; allocation method; treatment of internally recycled and exported scale and scrap

When constructing a foreground data package, every required qualifier shall be declared in dataset metadata, process notes, the reference-flow comment, the product description, or an equivalent data-package field. Missing required qualifiers make the reference-flow definition incomplete.

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_product_mass	Reference product and all steel feedstock, scale, and scrap rows	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Report dry as-shipped product mass, exclude packaging, and normalize all period totals to 1,000 kg of conforming reference product.
fuel_volume_conditions	Gaseous natural-gas input	Volume 93a60a56-a3c8-22da-a746-0800200c9a66	m3	Report the metered gas volume with temperature, pressure, and meter reference conditions; do not combine volumes measured at different reference conditions without documented conversion.
electricity_energy_basis	Alternating-current electricity inputs	Net calorific value 93a60a56-a3c8-11da-a746-0800200c9a66	MJ	Preserve metered electrical energy by process stage where submetering exists; document any conversion to MJ and the supplier-specific, regional, or national electricity dataset used upstream.
makeup_water_mass_balance	Descaling and cooling makeup-water rows	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Record only net boundary-crossing process-water mass. Convert a calibrated volume-meter record to mass only with a documented period-specific density; internal recirculating-loop flow shall not be counted repeatedly as fresh input.
wastewater_volume_balance	Treated-wastewater row	Volume 93a60a56-a3c8-22da-a746-0800200c9a66	m3	Record only net treated discharge crossing the boundary; internal recirculating-loop flow shall not be counted repeatedly as discharge.

5. System Boundary

Boundary Abstraction

Field	Value
declared_starting_condition	Either semi-finished non-alloy steel ready for reheating and hot rolling, or a wider hot-rolled non-alloy-steel flat product ready only for trimming, slitting, or cutting; the selected condition and upstream dataset are declared
starting_condition_role	Purchased or transferred technosphere input at the first foreground unit process
product_classification_scope	Finished non-alloy-steel flat-rolled product with width < 600 mm and no further work beyond hot rolling and permitted dimensional finishing
recursive_input_rule	Do not absorb an upstream hot-rolled steel input into the output reference flow. Record it as a separate technosphere input with its own upstream dataset and width/product-state qualifiers.
upstream_dataset_requirement	Link every semi-finished or wider hot-rolled steel input, fuel, electricity, and water supply to a geographically and technologically representative upstream dataset; prevent double counting of any upstream hot-rolling stage.
disclosure	Declare the starting condition, direct-rolling or wider-strip finishing route, included stages, hot-charge practice, furnace and mill type, finishing operations, internal recycling, waste-water treatment, site, geography, period, and all exclusions.

rule_id	Applies to	Rule	source_ids
boundary_stage_inclusion	foreground_gate_to_gate_boundary	Include every on-site stage used to transform the declared starting steel condition into conforming product: handling and conditioning, reheating where applicable, descaling, roughing and finish rolling, controlled cooling, coiling, and dimensional finishing; include associated water treatment and ancillary energy in the stages that use them.	ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017
boundary_exchange_completeness	foreground_gate_to_gate_boundary	Record all boundary-crossing materials, fuels, electricity, net water, measured or calculated emissions, wastes, and recovery outputs for included stages; do not replace atomic exchanges with a combined utility, fuel, waste, or emission row.	worldsteel-lci-methodology-2017
boundary_route_exclusivity	route_selection	Include reheating and hot-rolling stages only when performed by the foreground site. For a slitting/cutting-only route, link the wider hot-rolled input to an upstream dataset and exclude its already-modelled hot-rolling burdens from the foreground conversion stage.	ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017
boundary_excluded_operations	downstream_and_further_work	Exclude cold reduction, pickling-and-oiling, cladding, plating, coating, polishing, downstream fabrication, packaging, outbound transport, use, and end of life from the reference boundary unless separately added and reported outside this reference result.	un-cpc-3-0-structure-2025; ec-jrc-fmp-bref-2022

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
reheating_and_conditioning	Feedstock handling, conditioning, and reheating	conditional	Include when the foreground site hot-rolls semi-finished steel; omit for a slitting/cutting-only converter that receives a fully hot-rolled wider input.	Prepare and heat feedstock to rolling condition.	Mass of semi-finished steel charged and transferred to rolling.
hot_rolling_and_descaling	Descaling and hot rolling	conditional	Include when the foreground site performs hot rolling; omit when that stage is represented entirely by the upstream wider-strip dataset.	Remove scale and reduce steel to the required hot-rolled dimensions and properties.	Mass of hot-rolled strip leaving the finishing train.
cooling_and_finishing	Controlled cooling, coiling, and dimensional finishing	required	Always include; record only the cooling, coiling, trimming, slitting, and cutting operations actually performed.	Produce and release the conforming reference product at the mill gate.	1,000 kg net conforming reference product.

Process: Feedstock handling, conditioning, and reheating (reheating_and_conditioning)

Inputs

Product flows

Semi-finished non-alloy-steel feedstock (semi_finished_non_alloy_steel_feedstock)

Record the mass of slab or other declared semi-finished non-alloy steel entering the foreground hot-rolling route. The steelmaking and casting burdens belong to the linked upstream dataset.

• Selected flow: Continuously cast steel slab for flat rolling fa93b446-0340-4d7b-9f4d-e3f78789ea94
• Flow property / unit: Mass / kg
• Amount rule: Weighed net mass charged to reheating, reconciled for stock change and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_reheating_inputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Natural gas for reheating (reheating_natural_gas)

Record metered gaseous natural gas consumed by included reheating or equalisation furnaces. Disclose supply geography and gas-volume reference conditions.

• Selected flow: natural gas in the gaseous state 4f19ca0e-7b3b-11dd-ad8b-0800200c9a66
• Flow property / unit: Volume / m3
• Amount rule: Metered furnace natural-gas volume attributable to the accounting period and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_reheating_inputs
• Sources: ec-jrc-fmp-bref-2022

Alternating-current electricity for reheating (reheating_electricity)

Record metered alternating-current electricity used by feedstock handling, furnace auxiliaries, and conditioning equipment assigned to this process.

• Selected flow: alternating current 4d0361a3-56cc-45f9-aa42-bb9103285bf9
• Flow property / unit: Net calorific value / MJ
• Amount rule: Submetered electricity, or a documented engineering allocation of a shared meter, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_reheating_inputs
• Sources: worldsteel-lci-methodology-2017

Waste flows

Elementary flows

Outputs

Product flows

Waste flows

Furnace scale removed from reheated steel (reheating_furnace_scale)

Record the measured mass of scale collected from reheating and primary conditioning as an output of this process. State whether the net output is internally recycled, externally recovered, or disposed.

• Selected flow: Mill scale aad763e2-78ab-4fcb-8a3b-8d8525c9e6ca
• Flow property / unit: Mass / kg
• Amount rule: Measured net scale output after moisture correction and internal return, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_reheating_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Elementary flows

Fossil carbon dioxide from reheating (reheating_fossil_carbon_dioxide_to_air)

Record direct fossil carbon dioxide emitted by included reheating furnaces, using stack measurements or a documented fuel-carbon calculation without adding upstream fuel-supply emissions.

• Selected flow: carbon dioxide (fossil) 08a91e70-3ddc-11dd-923d-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured or verified calculated direct fossil CO2 emitted to air, normalized to 1,000 kg conforming reference product
• Value mode: Calculated value (calculated_value)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_reheating_outputs
• Sources: worldsteel-lci-methodology-2017

Nitrogen oxides from reheating (reheating_nitrogen_oxides_to_air)

Record direct stack nitrogen oxides from reheating as the facility reports them, retaining the reporting convention and converting to mass as NO2 only when that convention is documented.

• Selected flow: Nitrogen oxides to air, reported as NO2
• Flow property / unit: Mass / kg
• Amount rule: Stack-monitoring or test result multiplied by dry-gas flow and operating time, normalized to 1,000 kg conforming reference product
• Value mode: Calculated value (calculated_value)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_reheating_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Sulfur dioxide from reheating (reheating_sulfur_dioxide_to_air)

Record direct sulfur dioxide from reheating when measured or calculated from the actual furnace fuel sulfur balance; do not substitute a generic fuel-mix value.

• Selected flow: Sulfur dioxide to air
• Flow property / unit: Mass / kg
• Amount rule: Measured or verified calculated direct SO2 emitted to air, normalized to 1,000 kg conforming reference product
• Value mode: Calculated value (calculated_value)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_reheating_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Process: Descaling and hot rolling (hot_rolling_and_descaling)

Inputs

Product flows

Alternating-current electricity for hot rolling (hot_rolling_electricity)

Record metered alternating-current electricity used by descaling pumps, roughing and finishing stands, drives, roller tables, and process controls assigned to this process.

• Selected flow: alternating current 4d0361a3-56cc-45f9-aa42-bb9103285bf9
• Flow property / unit: Net calorific value / MJ
• Amount rule: Submetered electricity, or a documented engineering allocation of a shared meter, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_hot_rolling_inputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Makeup water for high-pressure descaling (descaling_makeup_water)

Record only net fresh or externally supplied makeup water entering the descaling circuit. Internal recirculating water is not counted again as a boundary input.

• Selected flow: Process Water 94a04f7e-2d5c-41f0-b182-d54a3b373a02
• Flow property / unit: Mass / kg
• Amount rule: Weighed net external makeup-water mass, or calibrated volume converted with documented period-specific density, entering the descaling circuit and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_hot_rolling_inputs
• Sources: ec-jrc-fmp-bref-2022

Waste flows

Elementary flows

Outputs

Product flows

Waste flows

Rolling-mill scale (rolling_mill_scale)

Record scale separated from descaling sprays, scale pits, and process-water treatment as one net waste or recovery output of this process. Moisture and oil content shall be reported with the measured mass.

• Selected flow: Mill scale 763bdad1-b443-428a-89b6-371a6807fc6c
• Flow property / unit: Mass / kg
• Amount rule: Measured net scale output after moisture correction and internal return, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_hot_rolling_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Hot-rolling steel scrap (hot_rolling_steel_scrap)

Record the net mass of cropped ends, cobbles, and other steel offcuts leaving this process as one chemically consistent non-alloy-steel scrap stream. Internal returns are balanced separately and not credited twice.

• Selected flow: Post-industrial steel scrap c143745d-be4f-4d8f-b403-2dcbfe685349
• Flow property / unit: Mass / kg
• Amount rule: Weighed net scrap output after internal return, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_hot_rolling_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Elementary flows

Particulate matter from hot rolling (hot_rolling_particulate_to_air)

Record direct particulate matter released from descaling, roughing, rolling, and finishing using the facility's declared particle metric and capture boundary.

• Selected flow: Particulate matter, particle size unspecified 0ce3dedb-caca-407b-a856-a90470eb8ec0
• Flow property / unit: Mass / kg
• Amount rule: Measured captured-stack plus quantified fugitive particulate mass, normalized to 1,000 kg conforming reference product
• Value mode: Calculated value (calculated_value)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Calculated from collection (calculated_from_collection)
• Collection protocol: cp_hot_rolling_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Process: Controlled cooling, coiling, and dimensional finishing (cooling_and_finishing)

Inputs

Product flows

Wider hot-rolled non-alloy-steel feedstock (wider_hot_rolled_non_alloy_steel_feedstock)

For a trimming, slitting, or cutting-only route, record the mass of fully hot-rolled wider non-alloy-steel flat product entering this process. Do not use this row for the direct narrow hot-rolling route.

• Selected flow: Non-Alloy Steel ce3ac926-5d6f-4558-9edc-67179d93dde4
• Flow property / unit: Mass / kg
• Amount rule: Weighed input mass, reconciled for stock change and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Route-specific (route_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_finishing_inputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Alternating-current electricity for cooling and finishing (finishing_electricity)

Record metered alternating-current electricity for cooling pumps, run-out tables, coilers, shears, slitters, and cut-to-length equipment actually used for the declared product route.

• Selected flow: alternating current 4d0361a3-56cc-45f9-aa42-bb9103285bf9
• Flow property / unit: Net calorific value / MJ
• Amount rule: Submetered electricity, or a documented engineering allocation of a shared meter, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Route-specific (route_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_finishing_inputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Makeup water for controlled cooling (cooling_makeup_water)

When controlled strip cooling is performed in the foreground route, record only net externally supplied makeup water entering the cooling circuit. Omit the row when no water-cooled hot strip is handled.

• Selected flow: Process Water 94a04f7e-2d5c-41f0-b182-d54a3b373a02
• Flow property / unit: Mass / kg
• Amount rule: Weighed cooling-circuit makeup-water mass, or calibrated volume converted with documented period-specific density, less documented transfers to other site systems and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Route-specific (route_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_finishing_inputs
• Sources: ec-jrc-fmp-bref-2022

Waste flows

Elementary flows

Outputs

Product flows

Conforming narrow hot-rolled non-alloy-steel product (reference_product_narrow_hot_rolled_non_alloy_steel)

This is the sole reference-product output. Report only product meeting the declared grade, dimensions, hot-rolled state, and finished width below 600 mm.

• Selected flow: Flat-rolled products of non-alloy steel, not further worked than hot-rolled, of a width of less than 600 mm 9705bbad-51bd-4ee8-af46-21324f57c577
• Flow property / unit: Mass / kg
• Amount rule: 1,000 kg net conforming reference product by definition
• Value mode: Fixed value (fixed_value)
• Specificity: Generic (generic)
• Normalization basis: 1,000 kg reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Method formula (method_formula)
• Sources: un-cpc-3-0-structure-2025; worldsteel-lci-methodology-2017

Waste flows

Finishing steel scrap (finishing_steel_scrap)

Record the net mass of edge trim and offcuts generated by coiling, trimming, slitting, or cutting. Internal returns are balanced separately and not credited twice.

• Selected flow: Post-industrial steel scrap c143745d-be4f-4d8f-b403-2dcbfe685349
• Flow property / unit: Mass / kg
• Amount rule: Weighed net finishing scrap after internal return, normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Route-specific (route_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_finishing_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Treated rolling-mill wastewater (treated_rolling_mill_wastewater)

Record the net treated process-water discharge attributable to the included hot-rolling and finishing stages after internal recirculation. Do not combine this discharge with scale or sludge outputs.

• Selected flow: Treated rolling-mill wastewater
• Flow property / unit: Volume / m3
• Amount rule: Metered net treated discharge assigned to the included stages and normalized to 1,000 kg conforming reference product
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1,000 kg conforming reference product
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_finishing_outputs
• Sources: ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Elementary flows

7. Allocation and Co-product Handling

rule_id	Applies to	Rule	source_ids
allocation_subdivision_first	shared_foreground_processes	Avoid allocation by submetering and subdividing reheating, rolling, cooling, finishing, water treatment, and ancillary services wherever their exchanges can be assigned directly.	worldsteel-lci-methodology-2017
allocation_shared_steel_products	multiple_conforming_steel_products	After subdivision, allocate remaining shared foreground exchanges among conforming hot-rolled steel products by net product mass over the same accounting period; disclose products, masses, and the calculation.	worldsteel-lci-methodology-2017
allocation_internal_recycling	internal_scale_and_scrap	Model scale and steel scrap returned within the declared system as internal exchanges and report only the net boundary output; do not assign an avoided-product credit to an internal loop.	worldsteel-lci-methodology-2017
allocation_exported_recovery	exported_scale_scrap_or_other_coproduct	For a net exported recovery material with a demonstrated market use, prefer system expansion based on a documented functionally equivalent substituted product and report sensitivity when material; otherwise report the output and treatment without an unverified substitution credit.	worldsteel-lci-methodology-2017

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_reheating_inputs	reheating_and_conditioning	Semi-finished steel, furnace natural gas, and reheating electricity	Weighbridge, production, gas-meter, and electricity-meter records	charged steel mass; beginning and ending stock; natural-gas volume and reference conditions; electricity; furnace and campaign identifiers	Reconcile calibrated meters and production records to the included furnace campaigns.	kg; m3; MJ	Batch or shift capture with monthly reconciliation	One representative continuous 12-month period; justify shorter or abnormal periods	All foreground reheating and conditioning equipment serving the declared product	Sum attributable records, apply documented shared-meter allocation, then divide by conforming reference-product mass and multiply by 1,000 kg.	Calibration certificates; stock reconciliation; meter extracts; production ledger; allocation worksheet
cp_reheating_outputs	reheating_and_conditioning	Furnace scale and direct combustion emissions	Scale weigh tickets, stack-monitoring records, fuel composition, and operating logs	wet and dry scale mass; moisture; internal return; CO2; NOx convention; SO2; stack concentration; dry-gas flow; operating time; fuel carbon and sulfur	Use calibrated weighing and stack data; calculations shall retain formula, factors, and measurement basis.	kg; kg/Nm3; Nm3; h	Batch or continuous capture with monthly reconciliation	Same period as product output	All included reheating emission points and scale collection	Calculate attributable period mass, subtract internal returns where relevant, normalize to 1,000 kg conforming product.	Laboratory results; monitor QA/QC; fuel certificates; weigh tickets; calculation workbook
cp_hot_rolling_inputs	hot_rolling_and_descaling	Rolling electricity and descaling makeup water	Electricity and water meter records	electricity; fresh makeup-water mass or volume and density; transfers; mill campaign and product identifiers	Use stage submeters; where unavailable, document engineering allocation from a shared calibrated meter; convert water volume to mass only with documented period-specific density.	MJ; kg; m3; kg/m3	Shift or daily capture with monthly reconciliation	Same period as product output	Roughing, finishing-train, descaling-pump, and roller-table equipment in scope	Sum net attributable inputs and normalize to 1,000 kg conforming product.	Meter calibration; density record; trend records; allocation worksheet; production ledger
cp_hot_rolling_outputs	hot_rolling_and_descaling	Rolling scale, hot-rolling steel scrap, and particulate matter	Weigh tickets, scale-pit records, scrap ledger, stack tests, and fugitive-emission assessment	scale mass, moisture and oil; scrap mass and internal return; particulate metric, captured mass, fugitive estimate, gas flow and time	Reconcile physical outputs with production and water-treatment records; document capture boundary.	kg	Batch or campaign capture with monthly reconciliation	Same period as product output	All included rolling stands, descalers, scale pits, and emission points	Calculate net boundary output by material, normalize to 1,000 kg conforming product, and keep recovery fate separate from quantity.	Weigh tickets; laboratory moisture/oil tests; monitor reports; scrap-return ledger
cp_finishing_inputs	cooling_and_finishing	Wider hot-rolled feedstock, finishing electricity, and cooling makeup water	Weighbridge, coil-tracking, electricity-meter, and water-meter records	wider input mass and dimensions; beginning and ending stock; electricity; makeup-water mass or volume and density; route and equipment identifiers	Link coil or batch identity through finishing; use calibrated meters and route-specific allocation; convert water volume to mass only with documented period-specific density.	kg; MJ; m3; kg/m3	Coil, batch, or shift capture with monthly reconciliation	Same period as product output	Cooling, coiling, trimming, slitting, and cutting equipment actually used	Sum route-attributable records and normalize to 1,000 kg conforming product.	Coil genealogy; dimensional inspection; calibration and density records; meter extracts
cp_finishing_outputs	cooling_and_finishing	Conforming product, finishing scrap, and treated wastewater	Product weigh tickets, quality release, scrap ledger, and discharge meter	product mass, grade, dimensions and disposition; scrap mass and internal return; treated discharge and assignment basis	Reconcile released product, nonconforming product, stock change, scrap, and net water discharge.	kg; m3	Coil or batch capture with monthly reconciliation	Same period as product output	Final product release, finishing scrap collection, and attributable wastewater treatment	Sum conforming product and net outputs; normalize all non-reference outputs to 1,000 kg conforming product.	Certified scales; inspection release; scrap tickets; discharge-meter records; reconciliation report

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
normalize_period_exchange	Every variable inventory row	Normalized amount = attributable period exchange / net conforming reference-product mass × 1,000 kg. Use one consistent accounting period and retain unrounded source totals.	attributable period exchange; net conforming reference-product mass	Exchange per 1,000 kg reference product	worldsteel-lci-methodology-2017
reconcile_steel_mass	Steel feedstock, reference product, scale, and scrap	Opening steel stock + steel inputs = closing steel stock + conforming product + nonconforming product + internally returned steel + net scale and scrap outputs + documented residual difference. Explain any material residual.	stock records; feedstock mass; product mass; scale; scrap; internal return	Steel mass-balance reconciliation	worldsteel-lci-methodology-2017
calculate_stack_emission_mass	Reheating CO2, nitrogen oxides, sulfur dioxide, and rolling particulate	Use direct mass monitoring where available; otherwise multiply concentration by compatible dry-gas volume or calculate from verified fuel composition and oxidation data. Preserve wet/dry basis, oxygen correction, reporting species, and time coverage.	concentration; gas flow; operating time; fuel composition; correction basis	Direct emission mass by atomic reported exchange	ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017
calculate_net_water_boundary	Descaling water, cooling water, and treated wastewater	Net water input and discharge shall exclude internal recirculation and separately identify transfers, evaporation, entrainment with scale/sludge, and meter imbalance.	intake meters; discharge meters; transfers; evaporation estimate; entrainment records	Net boundary-crossing water volumes	ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
dq_product_identity	Reference product and steel inputs	Retain grade, finished width and thickness, hot-rolled state, form, edge/surface condition, route, and coil or batch genealogy; demonstrate finished width < 600 mm and absence of excluded further work.	Classification and inspection records; un-cpc-3-0-structure-2025
dq_temporal_representativeness	All foreground records	Use one representative continuous 12-month period where practicable and document shutdowns, abnormal operation, maintenance, and any shorter-period justification.	Period coverage report; production ledger; worldsteel-lci-methodology-2017
dq_geography_technology	Foreground and upstream datasets	Identify site geography, furnace and mill technology, direct-hot-charge practice, finishing route, fuel supply, electricity supplier or grid, and water-treatment configuration; justify upstream representativeness.	Site description; supplier records; dataset metadata; worldsteel-lci-methodology-2017
dq_meter_and_calculation_traceability	Measured and calculated exchanges	Preserve raw meter extracts, calibration status, formulas, allocation worksheets, conversions, reporting conventions, and unrounded values sufficient for independent reproduction.	Calibration certificates; calculation workbook; QA/QC records
dq_completeness	Process inventory	Account for all known material, energy, water, emission, waste, and recovery exchanges by included stage; document every excluded flow against the study cut-off policy without using cut-off to omit all energy.	Completeness checklist and reconciliation; worldsteel-lci-methodology-2017

9. Validation Rules

rule_id	Applies to	Rule	source_ids
validate_product_boundary	reference_product	Confirm non-alloy steel, hot-rolled state, finished width < 600 mm, declared form and dimensions, and absence of excluded cold reduction or surface treatment.	un-cpc-3-0-structure-2025; ec-jrc-fmp-bref-2022
validate_reference_amount	reference_flow	Confirm exactly 1,000 kg net conforming product after normalization, excluding packaging, nonconforming material, and internally returned scrap.	worldsteel-lci-methodology-2017
validate_route_and_upstream_link	route_selection	Confirm that every performed stage is included once, every omitted upstream hot-rolling stage is represented by a linked input dataset, and no hot-rolling burden is double counted.	ec-jrc-fmp-bref-2022; worldsteel-lci-methodology-2017
validate_mass_and_water_balances	foreground_inventory	Reconcile steel mass and net water boundaries for the common accounting period; investigate and disclose residuals before release.	worldsteel-lci-methodology-2017
validate_uuid_and_atomicity	inventory_identity	Confirm every selected flow is one atomic exchange; directly re-read every adopted TianGong UUID at public state 100 and verify name, flow type, classification, property, unit group, state, geography, technology, and comment. Keep unresolved rows UUID-empty.
validate_allocation_and_recovery	shared_burdens_and_recovery_outputs	Confirm subdivision was attempted first, internal returns are not double credited, mass allocation uses contemporaneous net product outputs, and every system-expansion credit has documented functional equivalence and sensitivity where material.	worldsteel-lci-methodology-2017
validate_bilingual_alignment	bilingual_pcr_implementation	Confirm English and Chinese implementations have the same process, row, rule, source, UUID, controlled-token, and reference-flow identities.

10. Published Dataset Profile

Field	Value
dataset_role	secondary_dataset or background_dataset after methodology review, foreground verification, and publication approval
downstream_use	Cradle-to-gate or wider life-cycle models requiring a separately identified gate-to-gate narrow hot-rolled non-alloy-steel production dataset
allowed_use	Product systems matching the declared width class, steel grade family, hot-rolled state, route, geography, technology, accounting period, allocation, and upstream-dataset boundary
excluded_use	Cold-rolled, coated, clad, plated, pickled-and-oiled, alloy, stainless, electrical-steel, long-product, tube, or width >= 600 mm datasets; comparative assertions without a study-specific functional unit and review
required_metadata	PCR id; product identity and dimensions; route and starting condition; included processes; site and geography; period; furnace and mill technology; fuel and electricity supply; water boundary; allocation; internal recycling and export fates; source and dataset versions; unresolved UUID status
required_quality_disclosure	Primary-data share; temporal, geographic, and technological representativeness; meter/calibration status; calculation and allocation methods; mass- and water-balance residuals; cut-offs; uncertainty; missing data; review status
update_trigger	Change in product classification or state, route, furnace or mill technology, fuel or electricity supply, water treatment, allocation or recovery method, major input/output pattern, source evidence, TianGong UUID identity, or representative production period

11. Data Sources

Source id	Type	Reference	Used for
un-cpc-3-0-structure-2025	official_guidance	United Nations Statistics Division, CPC Ver. 3.0 Structure, 30 June 2025, code 41212. https://unstats.un.org/unsd/classifications/Econ/Download/In%20Text/CPC_Ver_3.0_Structure_30Jun2025.csv (retrieved 2026-09-03)	Official product-classification identity, non-alloy steel, hot-rolled state, and width threshold
ec-jrc-fmp-bref-2022	official_guidance	Aries, E. et al., Best Available Techniques (BAT) Reference Document for the Ferrous Metals Processing Industry, European Commission Joint Research Centre, EUR 31321 EN, JRC131649, 2022, doi:10.2760/196475. https://bureau-industrial-transformation.jrc.ec.europa.eu/sites/default/files/2022-12/FMP%20BREF_Final%20Version.pdf (retrieved 2026-09-03)	Narrow-strip definition; hot-rolling sequence; reheating fuels and emissions; descaling; rolling, cooling, coiling, and finishing; water circuits; scale and waste outputs
worldsteel-lci-methodology-2017	handbook	World Steel Association, Life cycle inventory methodology report for steel products, 2017, ISBN 978-2-930069-89-0. https://worldsteel.org/wp-content/uploads/Life-cycle-inventory-methodology-report.pdf (retrieved 2026-09-03)	Declared unit; gate-to-gate boundary; primary data, energy and emission completeness, quality, mass-balance validation, recovery and co-product handling