The Yarta Method
Every number, traced to its source.
This page is the method. It is versioned, it is conservative by default, and it changes only when the change is published.
Principles
Six rules every Yarta figure obeys.
If a number on a report cannot be explained by one of these, it does not go on the report.
Measured mass first
Tonnes from a weighbridge or a processor record. Counts are converted with a stated unit weight, and the unit weight carries its own status.
Recycled, Stored, Landfilled
Every tonne lands in one of three buckets. Recycled means baled or sorted material delivered to a licensed reprocessor, with a docket, and counts for you. Landfilled counts against you. Stored is neutral until it moves, and is never counted as recycled.
Steel is measured, not assumed
Steel recovered is the mass that leaves as scrap, credited only on the recycled portion of a load. The 99% mattress figure is Recycle Group's stated plant yield; a report prints the measured yield with its site and study date. Until measured figures replace them, the fractions in the library are marked group or assumption.
Two figures, never netted
Your Scope 3 Category 5 inventory figure and the avoided emissions are calculated on different bases and reported side by side. Avoided emissions are never deducted from the inventory, never called an offset, and never used for a carbon-neutral claim.
Conservative, cited and versioned
Every factor carries its source, its vintage and the library version it entered under. Where two credible figures exist, the claim uses the lower: the steel factor is the LCA net figure, not the gross, and an unaudited residual takes the higher mixed-waste landfill factor.
Pending means no claim
A stream with no avoided-emissions factor is reported as recovered tonnes with no estimate. It is marked pending, never guessed.
Two figures, never netted
Your inventory figure. The avoided figure. Kept apart.
The GHG Protocol's Category 5 guidance keeps avoided emissions out of the Scope 3 inventory: they may be reported, but separately, and never deducted. Every Yarta report carries both figures side by side, and a third, the landfill comparison, only as context.
Scope 3 Category 5 inventory
What the waste you hand over emits: the processor's energy to receive, sort, shred and bale it (supplier-specific), transport to the processor where it is done for you, and anything landfilled at the government's NGA landfill factor for its waste type. Making new product from the recovered material is the buyer's emissions, not yours.
Goes in your inventory · GHG Protocol waste-type-specific method
Avoided emissions
An estimate of the emissions avoided because recovered material displaces virgin production, from published life-cycle factors. Reported beside A with its source, vintage and boundary. Not deducted from A, not an offset and not a carbon-neutral claim.
Reported separately · NSW DECCW 2010 factors, flagged 2010
Landfill comparison
What A would have been had every tonne gone to landfill, at the same NGA factors. It shows what diversion did to your inventory. It is context only: never an inventory figure, never a saving to claim.
Context only · same factors as A
A · NGA landfill factors · t CO₂-e per tonne landfilled
| Waste type | Factor | Yarta categories that use it |
|---|
DCCEEW National Greenhouse Accounts landfill factors, as reproduced in the Commonwealth Emissions Reporting Framework 2024–25. Each report cites the NGA edition current at its reporting date. Mixed-stream factors apply only where composition is unknown.
A · Processing and transport · illustrative
| Line | Working value |
|---|---|
| Processing, supplier-specific. About 1,200 L of diesel a day at about 2.7 kg CO₂-e per litre, over 44 to 109 t a day, gives 0.03 to 0.07. | 0.05 t per t |
| Transport, where it is done or paid for on the customer's behalf. Rigid truck, distance-based. | 0.15 kg per t-km |
Both are replaced by metered fuel and electricity, divided by weighbridge throughput each month, and by fleet fuel data before the first customer report. Until then they are labelled illustrative wherever they appear.
Worked example · 1,000 mattresses · 120 km to the processor
Computed by the engineWith a one-week composition audit of the mattress residual (assumed here at 70% foam, 25% textile fibre and 5% wood), the residual factor would fall from the interim 1.3 to about 0.54, and Figure A from 74.7 t to about 34 t. The audit is the cheapest improvement in the method.
The factor library
Thirteen categories. Every factor with a status.
Generated from the same library the dashboard, calculator and report use. If it is not in this table, Yarta does not calculate with it.
| Category | Unit basis | Steel fraction | A · landfill factor per t landfilled | B · avoided factor per t recycled · source | Default pathway rec / sto / lan % | m³ per t | Status | Notes |
|---|
Scroll sideways for the full table
Steel fraction is the share of mass credited as recovered steel (steel fraction × steel recovery). The A column is the NGA landfill factor applied to any landfilled share, for the Category 5 inventory; interim means a mixed-waste factor used until a composition audit. The B column is the avoided-emissions factor, reported separately. The default pathway applies to a handover to Recycle Group unless the actual pathway is recorded on the docket. m³ per tonne is uncompacted volume, used for landfill volume avoided. Status: Reference is a published external source; Group is a Recycle Group or TMRC stated figure; Assumption is a Yarta working figure to be replaced; Pending means no avoided-emissions factor and no estimate.
The steel anchor factor · B
Steel, C&I/C&D. Conservative LCA net figure (includes collection and reprocessing impacts). worldsteel's gross figure of ≈1.5 t CO₂-e per tonne of scrap is higher; Yarta uses the conservative figure by default.
NSW DECCW 2010
The car equivalence · scale only
A family vehicle is assumed to emit 4.16 t CO₂-e over its lifetime (NSW DECCW 2010): cars permanently retired.
NSW DECCW 2010
Sources
Every source, named on the line it feeds.
A factor without a source is not in the library. A source without a link is a stated figure or a working value, and is labelled as one.
| Source | Title | Detail | Link |
|---|
Scroll sideways for the full table
How a figure is built
From a docket to a report, in eight steps.
The same sequence runs for every handover. The engine does the arithmetic. Nobody types a result.
Mass in
Every handover is recorded as mass. Weighed streams arrive as tonnes from the docket. Counted streams (mattresses, tyres, white goods, vehicles) are converted with the unit weight in the library, which carries its own status.
Pathway split
The mass is split across Recycled, Stored and Landfilled. The category's default pathway applies unless the handover's actual pathway is recorded, which it is whenever the docket says so.
Steel credited only on the recycled portion
For steel-bearing streams, steel recovered is mass × steel fraction × steel recovery, capped at the recycled tonnes. A landfilled or stored load claims no steel.
A · Category 5 inventory
Processing (tonnes handled × the processor's factor) plus transport (tonnes × km × the vehicle factor, where it is done for the customer) plus landfilled tonnes × the NGA landfill factor for the waste type. Stored material carries processing to date only. Material the customer evidences elsewhere carries no processing or transport from Yarta; anything of it landfilled still counts.
B · Avoided emissions, separately
Recovered steel × 0.44, plus non-steel recycled tonnes × the category factor. A category with no factor carries no estimate and is marked pending. B is printed beside A and is never subtracted from it.
Landfill volume avoided
What would have gone in (mass × m³ per tonne) less what did. Mattress residual is counted at 25% of its original volume because it is shredded first.
Recovery rate
Recycled tonnes ÷ tonnes handed over. Stored tonnes are not recycled, so they do not lift the rate until they move. Landfilled tonnes pull it down.
Yarta Score
Recovery rate, carbon intensity and evidence share combine into one number out of 100 with the published weights below. Computed by the engine, never typed.
The Yarta Score
One number. Three parts. Published weights.
A score out of 100 per customer per period, always shown with the tiles beneath it. Proposed at v0.1, published in full, and self-declared: not an accredited rating, certification or third-party verification.
Worked on the demo
Demo data · illustrative
Composition · proposed v0.1
| Component | Weight | Measured as |
|---|---|---|
| Material recovery rate | 60 | Recycled tonnes ÷ tonnes handed over |
| Carbon performance | 25 | Estimated avoided emissions (B) per tonne handed over, indexed to a reference intensity of 0.5 t/t and capped at 100%. The Category 5 inventory is never adjusted by the score. |
| Evidence quality | 15 | Mass-weighted share of tonnes backed by weighbridge dockets or processor certificates |
Material recovery rate 60% (recycled ÷ handed over) · Carbon performance 25% (estimated avoided emissions per tonne handed over, indexed to a reference intensity of 0.5 t/t, capped at 100%) · Evidence quality 15% (mass-weighted share backed by weighbridge dockets or processor certificates). Stored is neutral; Landfilled counts against through the recovery rate. The Category 5 inventory is never adjusted by the score.
Bands
| Band | Score |
|---|---|
| Leading | 80 and above |
| Strong | 60 to 79 |
| Developing | 40 to 59 |
| Starting | below 40 |
The Yarta Score is self-declared under Yarta's own published method, versioned with the Yarta Method. It is not an accredited rating, certification or third-party verification, and it is never shown with a tick, a shield or the word "certified". The weights may change; when they do, the change is published in the log below and earlier reports keep the version they were issued under.
Targets, potential and help
Where you are, where the targets are, and what would close the gap.
Beside the Yarta Score, every dashboard and report shows the score at the 2030 targets and an estimate with the recommended help done. The help comes from published rules, so the same figures always give the same recommendations, and any provider can do the work.
Now
—
The Yarta Score for the period, from the handovers Yarta has entered and verified.
At the 2030 targets
—
The same period with each target met: an 80% resource recovery rate (National Waste Policy Action Plan, 2024) and every tonne on Grade A evidence. Carbon performance stays as it is, because there is no target for it.
With Yarta help · estimate
—
The same period with the assumed effect of every recommended item applied in full, recalculated by the same engine as the score. An estimate, not a promise or a guarantee.
Worked on the demo data: Hepburn Shire Council hard waste program, illustrative. The rules below are proposed under the Yarta Method v1.0 draft.
| Help | Recommended when | Assumed effect · estimate | Delivered by |
|---|
Scroll the table sideways →
The roadmap
The report carries the roadmap as its third page: the three numbers, the projected score month by month, and the plan by quarter.
Independence
Evidence grades
Evidence is graded, not assumed.
A weighbridge docket and a customer's say-so are both recorded. They do not carry the same weight.
Grades A, B and C
Proposed · Yarta Method v1.0 draftWeighbridge docket or processor certificate
Counts in full toward the Yarta Score and every tile.
Signed count sheet or contractor report
Counts, and is flagged on the ledger and the report so a reader can see what it rests on.
Customer statement without documentation
Recorded on the ledger. Does not count toward the Yarta Score until evidence is supplied.
The Yarta Score's evidence-quality component is the mass-weighted share of tonnes backed by Grade A evidence. A Grade C entry can be upgraded at any time: send the docket, the operator attaches it, and the tonnes start counting.
Versioning and change log
The method changes only when the change is published.
Every report states the version it was calculated under. A later version never rewrites an earlier report.
| Version | Date | Change |
|---|---|---|
| v1.0 draft | 28 September 2026 | Two figures, never netted. Figure A: Scope 3 Category 5 inventory, GHG Protocol waste-type-specific method, NGA landfill factors, illustrative processing and transport values. Figure B: avoided emissions from NSW DECCW 2010 factors, reported separately and flagged 2010. Figure C: landfill comparison, context only. Recycled defined as delivered to a licensed reprocessor. The 99% steel figure treated as a stated plant yield until a dated study. Yarta Score unchanged at proposed v0.1, labelled self-declared. Added, proposed: the score at the 2030 targets, an estimated score with recommended help, the published help rules and the roadmap page on the report. |
| v0.1 draft | 27 September 2026 | Initial factor library. NSW DECCW 2010 reference factors. Recycle Group mattress figures. Working assumptions flagged as assumptions. Pending streams carry no carbon. |
Locked before the first customer report
- Metered processing fuel and electricity, divided by weighbridge throughput each month, replacing the illustrative 0.05 t CO₂-e per tonne; fleet fuel data replacing the illustrative transport factor.
- A composition audit of the mattress residual, replacing the interim mixed C&I landfill factor.
- A dated steel yield study (site, date, sample size, re-tested annually) behind the 99% figure, and steel recovery by stream from processing records.
- Measured unit weights from the Recycle Group weighbridge, replacing the stated averages for mattresses, tyres, white goods and vehicles.
- A refresh of the 2010 avoided-emissions factors, from an Australian life-cycle source, before any report relies on them.
- A pathway for coloured timber, e-waste and textiles, so those streams leave Pending, and a 12-month ageing rule for stored material.
- The TMRC per-size mattress table reconciled with the group's 30%-of-mass steel figure.
- A decision on third-party limited assurance of the weighbridge-to-report chain. Until then, every report says it is not independently assured.
Until these are locked, the version reads "draft" on every page that uses it, and no customer report is issued.
The Yarta Method
Want the method pack?
The factor library, the sources and the change log as one document, with worked examples. Ask for it when you book a walkthrough, or run your own numbers through the calculator first.