Mechanically softened uncoated sheep leather from dyed crust

1. Scope and Applicability

This PCR covers a bounded dry mechanical finishing route for hairless sheep or lamb leather: receive already chromium-tanned, retanned, dyed, fat-liquored and dried crust leather at a documented moisture condition suitable for mechanical softening; stake, optionally dry-mill without added chemicals, trim, grade and accept uncoated leather for further garment or glove fabrication. The representative product is dyed sheep nappa without a surface coating. The process sequence and acceptance specification are site and product specific [assomac-finishing; goldpanel-production]. The route begins after upstream wet processing and drying. It excludes raw skins, wet-blue inputs, on-site wet retanning/dyeing/fat-liquoring, deliberate water addition, further thermal drying, coating, buffed suede/nubuck, patent, metallized, composition leather, goats and other species, and manufacture/use of leather articles. Any such operation requires a separately reviewed route expansion with its individual exchanges. CPC 29130 also includes other skins and composition leather; this PCR does not establish coverage of that whole subclass [un-cpc-2025].

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.food-products-beverages-and-tobacco-textiles-apparel-and-leather-products.leather-and-leather-products-footwear.mechanically-softened-uncoated-sheep-leather
classification_refs	CPC 3.0:29130; narrower scope; classification context only
covered_products	Uncoated hairless chrome-tanned dyed sheep/lamb leather from received conditioned crust
excluded_products	Goat/kid leather; composition leather; wet processing; coatings; synthetic leather; fabricated articles
representative_product	Mechanically softened uncoated dyed sheep nappa for garment fabrication
production_route	Conditioned dyed crust reception → staking → dry milling when used → trimming/grading → net mass acceptance and pack-out
market_state	Dry saleable leather at declared equilibrium moisture; no fabricated article or lifetime claim

3. Reference Flow

Field	Value
What	Supply uncoated mechanically softened sheep leather for further fabrication
How much	1 kg net accepted leather at declared conditioning state
How well	Declared sheep/lamb origin, chrome tannage, pre-existing dye/fat-liquor, thickness, softness and purchaser acceptance specification; no assumed quality equivalence to another route
How long or cycle	One declared homogeneous factory reporting pool covering included lots, failed work and rework; no consumer service duration assigned
reference_flow_link	finished_leather

Field	Value
Reference amount	1
Reference product flow	Uncoated chrome-tanned dyed sheep leather
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	species; supplier and lot; incoming processing state; chrome tannage; dye/fat-liquor composition evidence; incoming and output moisture; uncoated surface; thickness and softness acceptance; process sequence; geography and meter voltage; waste destination; upstream gaps

Declare every required qualifier in the foreground dataset metadata or process description.

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_mass	reference product	Mass	kg	Use cp_mass to weigh accepted net leather at the declared conditioning state, excluding packaging, waste and lower-grade output. Every inventory denominator is the same 1 kg reference flow.
area_conversion	dyed_sheep_crust; finished_leather	Mass	kg	Retain supplier area or piece counts as auxiliary records. Obtain traceable same-lot paired mass and area/count measurements at the declared moisture and thickness; only these observations support a mass conversion. Never impose a generic kg/m2 or kg/skin coefficient or change a public flow property to Mass.
electricity_units	electricity_lv; electricity_mv	Net calorific value	MJ	Preserve referenced property 93a60a56-a3c8-11da-a746-0800200c9a66 and energy unit group 93a60a57-a3c8-11da-a746-0800200c9a66. Collect kWh then use exactly 1 kWh = 3.6 MJ; no fuel mass or heating-value surrogate.
moisture_state	reference product	Mass	kg	Reference mass includes moisture at declared acceptance condition; it is not oven-dry collagen mass. Record moisture fractions separately and reconcile evaporation; no automatic dry-mass redefinition.

5. System Boundary

rule_id	applies_to	rule	source_ids
boundary_route	foreground	Include reception, storage, handling, all mechanical softening passes, trimming, quality grading, rework, pack-out, extraction and attributable site electricity. Mechanical finishing is distinct from upstream wet crust production [assomac-finishing; goldpanel-production].	assomac-finishing; goldpanel-production
boundary_upstream	upstream	Link purchased crust to a compatible supplier dataset including its actual animal production, slaughter/skin recovery, preservation, unhairing, tanning, retanning, dyeing, fat-liquoring and drying scope; disclose any upstream gap. Do not repeat those burdens in the finishing foreground or claim complete cradle-to-gate from this foreground alone.	goldpanel-production
boundary_water	water and releases	No deliberate water input, wet washing or wet wastewater generation belongs to the defined dry route. Disclose moisture entering in crust, moisture retained in accepted leather, and measured evaporative loss; distinguish it from liquid effluent. Actual wet cleaning or conditioning makes a route extension necessary, with separate technosphere water, effluent and measured direct-release rows; never replace effluent by water-resource elementary flows.	assomac-finishing
boundary_release	air and waste	Collected chrome-bearing leather fibre dust and trimmings are technosphere waste transfers. Airborne particulate and evaporated water are separate conditional environmental exchanges, only supported by measurement or an independently closed moisture balance; no mandatory chromium, solvent or combustion emission is inferred. Declare actual receiving subcompartment and downstream treatment.	assomac-finishing

Boundary Abstraction

Field	Value
declared_starting_condition	Purchased already conditioned, dyed, fat-liquored, chrome-tanned dry sheep crust; no on-site wet processing
starting_condition_role	Foreground manufacturing input after upstream crust preparation
product_classification_scope	A narrower dry mechanical sheep-leather route within CPC 29130
recursive_input_rule	Already finished same-category leather rework must retain the previous production dataset and separate rework demand; do not count it as virgin crust or recurse indefinitely
upstream_dataset_requirement	Compatible conditioned sheep crust, electricity and actual packaging supply; matched waste treatment; disclose missing animal and tannery stages
disclosure	Species, tannage, dye/fat-liquor, moisture, partial boundary, on-site passes, direct emissions, voltage, treatment and supplier upstream scope

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
reception	Dyed crust reception and handling	required	All covered lots	foreground manufacturing	per 1 kg reference flow
softening	Staking and dry mechanical softening	required	Staking required by selected route; dry milling only when actually used, without added chemicals	foreground manufacturing	per 1 kg reference flow
acceptance	Trimming, grading, acceptance and pack-out	required	All covered lots; record carton only when used	foreground manufacturing	per 1 kg reference flow
utilities	Attributable electricity and extraction service	required	All covered lots; choose voltage-specific supply row by actual meter boundary	foreground manufacturing	per 1 kg reference flow

Process: Dyed crust reception and handling (reception)

Inputs

Product flows

Chrome-tanned dyed fat-liquored dry sheep crust leather (dyed_sheep_crust)

Weigh received net sheep crust for the lot; document species, tanning chemistry, dye/fat-liquor already present, moisture and thickness. Raw sheep skin, wet blue and unspecified animal leather are not equivalent incoming states.

• Selected flow: Chrome-tanned dyed fat-liquored dry sheep crust leather
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_material; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_material
• Sources: goldpanel-production

Outputs

Process: Staking and dry mechanical softening (softening)

Inputs

Outputs

Waste flows

Collected chrome-tanned dyed sheep leather fibre dust (captured_leather_dust)

Conditional: actual dust extracted during dry milling, staking or handling. Weigh collector discharge at declared moisture and record chromium-bearing status and licensed destination; do not treat captured dust as an air release.

• Selected flow: Collected chrome-tanned dyed sheep leather fibre dust
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_waste; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_waste
• Sources: assomac-finishing

Elementary flows

Particulate matter, particle size unspecified (particulate_air)

Conditional: a measured total particle mass release to air with unspecified particle size and air subcompartment. Document sampling method, flow rate and duration after capture. If size fractions or urban/high-stack location are established, choose separately verified compatible identities; do not label total dust PM10 or add overlapping fractions.

• Selected flow: Particulate matter, particle size unspecified 0ce3dedb-caca-407b-a856-a90470eb8ec0
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_air; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: assomac-finishing

water vapour (water_vapour_air)

Conditional: positive water evaporation from received leather supported by exhaust measurement or closed lot moisture balance. Identity is emission to air, unspecified subcompartment, not freshwater discharge or water extraction. No default evaporation percentage applies.

• Selected flow: water vapour fe0acd60-3ddc-11dd-ac04-0050c2490048
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_moisture; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_moisture
• Sources: assomac-finishing

Process: Trimming, grading, acceptance and pack-out (acceptance)

Inputs

Product flows

Paper box (paper_box)

Conditional: actual cut, folded and laminated paper box used for delivery. Weigh net box mass and disclose construction; other packaging components require their own atomic rows. Keep all packaging mass outside the leather reference mass.

• Selected flow: Paper box 12d5d744-7725-4dbc-b102-43c80547f777
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_material_acceptance; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_material_acceptance
• Sources: goldpanel-production

Outputs

Product flows

Uncoated chrome-tanned dyed sheep leather (finished_leather)

Accept the uncoated dyed sheep leather against the declared purchaser specification. Weigh net accepted output at documented conditioning/moisture state, excluding packaging and rejected lots.

• Selected flow: Uncoated chrome-tanned dyed sheep leather
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: 1 kg
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_mass
• Sources: goldpanel-production

Downgraded uncoated chrome-tanned dyed sheep leather (downgraded_sheep_leather)

Conditional: a distinct saleable lower grade leaving the boundary. Record its actual quality, mass, moisture, price and buyer; internal rework is not an additional saleable output.

• Selected flow: Downgraded uncoated chrome-tanned dyed sheep leather
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_products; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_products
• Sources: goldpanel-production

Waste flows

Chrome-tanned dyed sheep leather trimmings (leather_trimmings)

Conditional: actual cut-off leather transferred as waste. Weigh net mass and document composition, chromium content evidence, moisture and destination. Material sold as a co-product must be declared and allocated rather than silently assigned zero burden.

• Selected flow: Chrome-tanned dyed sheep leather trimmings
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Unit group: 93a60a57-a4c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_waste_acceptance; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_waste_acceptance
• Sources: goldpanel-production

Process: Attributable electricity and extraction service (utilities)

Inputs

Product flows

Alternating current (electricity_lv)

Conditional: only CN grid-average consumption mix delivered to the user at <1 kV. Meter staking, milling, handling, extraction and attributable storage/packing electricity; exclude supply already counted by the medium-voltage row. Other geography or supply requires another verified flow.

• Selected flow: Alternating current 50657322-939c-4829-a87b-47c093bfa6a7
• Flow property / unit: Net calorific value 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Unit group: 93a60a57-a3c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_energy; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_energy
• Sources: assomac-finishing

Alternating current (electricity_mv)

Conditional: only CN grid-average consumption mix delivered to the user at 1–35 kV. Retain the actual purchased meter boundary and allocate attributable demand. Do not count the same transformer feed again as low-voltage grid supply.

• Selected flow: Alternating current 3d76981f-964a-4865-b588-0e067a2a1163
• Flow property / unit: Net calorific value 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Unit group: 93a60a57-a3c8-11da-a746-0800200c9a66
• Amount rule: Collect the actual attributable lot quantity using cp_energy; after declared allocation, sum attributable quantities over the same homogeneous reporting pool, including wholly rejected lots and rework, then divide once by that pool’s positive accepted net reference-product kg from cp_mass.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_energy
• Sources: assomac-finishing

Outputs

7. Allocation and Co-product Handling

rule_id	applies_to	rule	source_ids
allocation_subdivide	shared foreground	First segregate lots, metered equipment time and rework. Allocate shared electrical demand by measured causal equipment consumption/time and retain idle demand consistently; never use unsupported standard percentages.
allocation_products	saleable grades	Record every saleable grade and its measured mass. Prefer process subdivision or justified physical relationships; if no defensible physical relationship explains economic grading, use same-period net sales values for residual joint burdens, disclose basis and test mass allocation sensitivity. This is a declared foreground modelling choice, not a tannery-wide default or source-derived factor.
allocation_waste	leather residues	Waste status follows actual disposal/sale contract. Include waste handover and matched treatment; do not grant avoided virgin leather or energy credits inside this attributional foreground. Reworked pieces stay inside the lot until final acceptance; count their processing once.

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_mass	acceptance	finished_leather	weighing and acceptance	lot; net accepted leather mass; tare; moisture; thickness; softness; grade; calibrated scale; acceptance record; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Weigh accepted net leather on a calibrated scale after declared conditioning; exclude all packaging, waste and lower grades. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_material	reception	dyed_sheep_crust	input issue and net weighing	lot; supplier; species; incoming processing state; tannage; dye/fat-liquor evidence; material name; issued/returned mass; moisture; optional area/count; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Reconcile calibrated net weighing, store issues, returns and supplier records for each atomic material; paired same-lot measurements support any area/count conversion. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_material_acceptance	acceptance	paper_box	input issue and net weighing	lot; supplier; material name; paper/board and packaging construction; supplied state; issued/returned net mass; moisture; box count; tare; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Reconcile calibrated net weighing, store issues, returns and supplier records for each atomic material; paired same-lot measurements support any area/count conversion. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_energy	utilities	electricity_lv; electricity_mv	electricity metering	lot; geography; purchased voltage; meter boundary; kWh opening/closing; operating/idle time; route; equipment; rework; allocation basis; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Read calibrated submeter or reconcile site meter to actual equipment load/time; retain losses inside the purchased boundary without double counting. Convert kWh to MJ at 3.6. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	MJ	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_waste	softening	captured_leather_dust	waste weighing and transfer	lot; separate dust/trimming mass; moisture; chromium evidence; container tare; transfer date; receiver; treatment; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Weigh each waste separately on calibrated scale, reconcile collector/trimming logs and actual transfer records; prohibit mixing with liquid effluent. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_waste_acceptance	acceptance	leather_trimmings	waste weighing and transfer	lot; separate dust/trimming mass; moisture; chromium evidence; container tare; transfer date; receiver; treatment; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Weigh each waste separately on calibrated scale, reconcile collector/trimming logs and actual transfer records; prohibit mixing with liquid effluent. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_air	softening	particulate_air	measured release	lot; sampling method; particulate size scope; concentration; exhaust flow; duration; capture state; air subcompartment; uncertainty; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Measure concentration and matched exhaust flow/time after dust capture; integrate actual release and document location. No particulate identity implies a mandatory release. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_moisture	softening	water_vapour_air	moisture balance or exhaust measurement	lot; received wet mass; accepted mass; lower-grade mass; dust/trimming mass; respective moisture fractions; stock change; exhaust vapour measurement; uncertainty; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Measure mass and moisture separately for all lot outputs and stocks; independently reconcile the moisture balance or use calibrated exhaust vapour measurement. Unclosed moisture cannot be assumed evaporation. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence
cp_products	acceptance	downgraded_sheep_leather	saleable grade and valuation	lot; grade; net mass; moisture; actual sales value; buyer; rework history; reporting-pool ID; all included lot IDs; wholly rejected lots; rework links; grade-allocation ledger	Weigh each saleable lower grade and reconcile same-period sales invoices; separate internal rework from actual outgoing products. Retain raw lot quantities, allocate genuine co-product burdens as declared, and include reference-product-attributable failed-lot quantities in the same homogeneous pool before division by its positive accepted reference-grade kg; if that total is zero, preserve absolute records and require review.	kg	each lot and relevant operating interval	declared representative production period including idle time and rework; disclose dates and exclusions	covered finishing site and matched lot	per 1 kg reference flow	calibration; lot reconciliation; raw records; uncertainty; supplier and transfer evidence

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
lot_normalization	all inventory rows	Define a homogeneous reporting pool by site, period, species, incoming processing state, conditioning and reference-grade specification; retain individual lot records and use allocation_subdivide/allocation_products for genuinely distinct saleable grades. For each row, sum the reference product’s attributable measured or calculated quantities across all included lots, including wholly rejected lots, idle activity and rework, in its native unit; divide once by the same pool’s accepted reference-grade net kg from cp_mass. Count finally accepted reworked output once; lower grades, packaging and waste never enter that denominator. Never divide a zero-output lot separately or discard its attributable burdens. The pool denominator must be positive; if the whole pool has no accepted reference product, retain absolute inventories and any evidenced co-product allocation, report reference-product normalization unavailable and require review, with no fabricated mass or zero burden.	cp_mass; applicable collection protocol	exchange per 1 kg reference flow
meter_conversion	electricity_lv; electricity_mv	Convert allocated kWh readings to MJ using the exact unit identity 1 kWh = 3.6 MJ, then aggregate all included lots and divide by the same positive accepted reference-grade kg of the declared reporting pool, retaining wholly rejected-lot and rework electricity.	cp_energy; cp_mass	MJ per 1 kg reference flow
release_integration	particulate_air	Integrate matched measured concentration × exhaust volume over the sampled operating period, convert to kg with explicit units, and reconcile unsampled periods before normalization.	cp_air; cp_mass	kg particulate per 1 kg reference flow
moisture_reconciliation	water_vapour_air	Subtract measured retained-output moisture and net stock moisture increase from received moisture; require independent closure and no other liquid exits before assigning the positive remainder to atmospheric vapour. Otherwise use direct exhaust measurement or retain a disclosed data gap.	cp_moisture; cp_mass	kg evaporated water per 1 kg reference flow

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
quality_identity	all inventory rows	Verify species, processing state, chemical composition, public UUID reference property and official Chinese flow name; no rawhide/crust/finished-leather substitution.	Supplier declarations; direct flow/property/unit records
quality_measurement	foreground	Use actual recipes and conditions from supplier/site records; no invented tanning recipe, energy, loss, net yield, quality or service life. Confirm temporal representativeness and material/dry-solids/moisture reconciliation.	Calibration; acceptance tests; mass balances; raw dates; uncertainty
quality_completeness	boundary	Record all actual auxiliaries and packaging as additional atomic exchanges. Distinguish absent activity from unmeasured activity; disclosed gaps do not become zero. Wet/coated routes invalidate applicability.	Route audit; procurement ledger; waste/air records; missing-data register

9. Validation Rules

rule_id	applies_to	rule	source_ids
validate_scope	reference product	Confirm sheep/lamb origin, received dyed fat-liquored chrome crust, no deliberate water addition, no new wet processing, thermal drying or coating; otherwise this PCR is not applicable.	un-cpc-2025; goldpanel-production
validate_reference	finished_leather	Require exact reference-product/output-row name match, positive measured accepted reference-grade net kg for the same reporting pool, declared moisture and all qualifiers; zero-output lots remain included in the numerator. Check the same 1 kg reference basis in both languages and all collection protocols. If the entire pool has zero reference-grade output, retain absolute quantities and report normalization unavailable for review.
validate_balance	foreground	Reconcile received solids and water with accepted output, lower grades, residues, evaporation and stock changes, using measured uncertainty. No invented universal yield or tolerance; unexplained imbalance remains a finding.
validate_identity	UUID rows	Recheck published state-100 identity, reference property/unit group, voltage/geography and air subcompartment. Blank UUIDs remain explicit identity gaps; neither candidate check nor identity verification grants scientific approval.
validate_completeness	dataset	Require actual quantities and protocols for applicable rows, evidence for non-applicable rows, allocation basis and uncertainty disclosure, matched upstream datasets and treatment destinations. Never call this partial foreground complete cradle-to-gate.

10. Published Dataset Profile

Field	Value
dataset_role	Foreground dry mechanical sheep-leather finishing process
downstream_use	secondary_dataset; background_dataset, after independent review and supplier linking
allowed_use	Matching uncoated dyed chrome-tanned sheep leather finishing, with actual moisture and upstream state
excluded_use	Whole CPC coverage; integrated tanning; composition leather; coated or other-species leather; product comparison or consumer lifetime without further review
required_metadata	All reference qualifiers; lot dates; net output; route; voltage; supplier upstream stages; allocation; moisture; waste and release compartments
required_quality_disclosure	Partial foreground boundary; data gaps and blank identities; actual collection coverage; uncertainty; missing upstream animal/tannery stages; review state
update_trigger	Species, supplier state, tannage, formulation, moisture, route, coating, voltage or significant collection changes

11. Data Sources

Source id	Type	Reference	Used for
un-cpc-2025	official_guidance	UNSD, CPC Ver. 3.0 Explanatory Notes, 30 June 2025, printed p. 134. https://unstats.un.org/unsd/classifications/Econ/Download/In%20Text/CPC_Ver_3.0_Exp_Notes_30Jun2025.pdf	Classification boundary only; subclass has a title without further process explanation
assomac-finishing	handbook	Assomac, A03 - Finishing machinery, undated publisher page, A03.01–A03.03, A03.08. https://assomac.it/en/technological-guide/tanning-machinery/a03-finishing-machinery/	Qualitative mechanical softening, controlled moisture and extraction options; no universal sequence or numeric performance; dry route is a declared subset
goldpanel-production	handbook	GoldPanel Group, Leather Tannery Department Production Process, undated publisher page; Dry Crusting, Finishing, Quality Inspection, Types of Leather. https://goldpanelgroup.com/page/site-page/leather-tannery-department-production-process.html	Sheep nappa manufacturing context, upstream dyed-crust state and product-dependent finishing/grade/rework; manufacturer-specific evidence, not industry default