The GLEC Framework — Practical Implementation of ISO 14083
What Is the GLEC Framework?
The Global Logistics Emissions Council (GLEC) Framework — full title: Global Logistics Emissions Council Framework for Logistics Emissions Accounting and Reporting — is the primary industry-led methodology for the consistent calculation and reporting of GHG emissions across global multi-modal supply chains.
Smart Freight Centre (SFC), a global non-profit organisation, developed it together with a voluntary partnership of over 150 companies, industry associations, and technical experts.
How is GLEC related to ISO 14083?
The GLEC Framework and ISO 14083 are closely connected:
- The GLEC Framework served as the foundational basis for ISO 14083, which began in 2019 to establish an internationally accepted format for transport carbon accounting
- Today, GLEC Framework v3 fully aligns with ISO 14083:2023 — the two agree on methodology, terminology, and calculation rules
- While ISO 14083 is the formal international standard, the GLEC Framework acts as the practical implementation guide: more accessible, with default datasets and toolkits that allow companies to achieve ISO-compliant calculations without starting from scratch
In short: ISO 14083 sets the rules; the GLEC Framework provides the data and guidance to apply them.
What the GLEC Framework Adds
Beyond the core ISO 14083 requirements, the GLEC Framework adds several practical layers:
| Addition | Detail |
|---|---|
| Extensive default datasets | A comprehensive database of default fuel efficiency and emission intensity factors for cases where operators lack measured primary data |
| Air pollutant modules | Methods for measuring black carbon, NOₓ, SOₓ, and particulate matter — areas that ISO 14083 does not fully address |
| Sector-specific guidance | Tailored instructions for the European chemical industry, mail and parcel services, and other sectors |
| Data quality indicator | A tiered ranking system (1 to 4) so stakeholders can assess the reliability of any reported figure |
| GLEC Declaration format | A standard reporting output that companies issue to customers |
GLEC Framework Emission Factors and Datasets
The Framework provides Well-to-Wheel (WTW) emission factors, broken into WTT and TTW components. These factors draw on internationally recognised sources, including:
- IEA (International Energy Agency)
- IPCC (Intergovernmental Panel on Climate Change)
- IMO (International Maritime Organization)
- National databases: UK, USA, China
Crucially, Smart Freight Centre sets default datasets as conservative values — typically higher than actual operator performance. This design choice stops operators from underestimating emissions and creates a clear incentive to collect more accurate primary data. In turn, operators who gather real shipment data consistently produce lower, more accurate figures.
Logistics Emissions Allocation Methodologies
The GLEC Framework applies the same allocation principles as ISO 14083. However, it makes these principles concrete through practical rules for each transport scenario:
- Mass-based — the primary allocation metric is the actual shipment mass
- Temperature control — cooling energy and refrigerant leakage apply only to temperature-controlled cargo in mixed loads
- Passengers vs freight — in combined transport such as ferries or passenger aircraft, operators split emissions using passenger equivalents (peq) based on mass and volume
- Travel class — rail and air allocation accounts for differences in area and occupancy between classes
Transport Modes for Logistics Emissions
The GLEC Framework covers the full transport chain across all major modes and logistics nodes:
| Category | Modes |
|---|---|
| Land | Road, Rail |
| Water | Maritime (Sea), Inland Waterways |
| Air | All aircraft types including freighters and belly cargo in passenger planes |
| Fixed | Pipelines, Cable Cars |
| Nodes | Logistics hubs — warehouses, terminals, distribution centres |
How Logistics Operators Use It
In practice, operators implement the framework through a structured bottom-up process. The steps fall into two groups: first measuring emissions correctly, then using that data for reporting and commercial decisions.
Measuring and Tracking Emissions
- TCE Breakdown — Subdivide the transport chain into Transport Chain Elements — for example, a single truck leg, a single hub stay, or a single sea leg
- Categorisation — Group similar operations into TOCs or HOCs to calculate average emission intensities, rather than repeating individual shipment calculations each time
- KPI tracking — Use emission intensity (kgCO₂e per tonne-km) as the key performance indicator. This metric lets operators measure the impact of route changes, fleet upgrades, or modal shift over time
Reporting and Commercial Use
- GLEC Declaration — Issue a transparent declaration to customers showing absolute emissions, the data quality tier used, and the calculation method. As a result, customers can use this document directly in their own CSRD Scope 3 disclosures
- Procurement decisions — Similarly, buyers use GLEC-declared data to compare the carbon footprint of different carriers and modes on equal terms, making emissions performance a commercial differentiator
GLEC Framework Recognition and Endorsement
The GLEC Framework holds broad recognition from key organisations and industry leaders. For example:
- CDP explicitly recommends it as the standard for logistics emissions disclosure
- The European Commission recognises it in CSRD guidance as an acceptable methodology for Scope 3 transport emissions reporting
- The largest global logistics operators — DHL, Maersk, Kuehne+Nagel, and DB Schenker — use it as their primary emissions reporting framework
Why It Matters for CO2Path
CO2Path closely follows GLEC Framework developments. Specifically, the platform’s emission factor library draws on GLEC default datasets where operators lack primary data, applies GLEC-aligned allocation rules, and produces outputs in GLEC Declaration format. Consequently, CO2Path outputs fit directly into the reporting workflows of large shippers and logistics service providers without additional conversion or reformatting.
Frequently asked questions
The GLEC Framework (Global Logistics Emissions Council Framework) is an industry-led methodology for calculating and reporting GHG emissions from logistics operations. Today, it serves as the practical implementation guide for ISO 14083:2023 and is used by major global logistics operators including DHL, Maersk, and Kuehne+Nagel.
ISO 14083 is the formal international standard that defines the rules for freight emissions calculation. In contrast, the GLEC Framework is the practical companion that provides the data — default emission factors, transport mode datasets, a data quality tier system, and sector-specific guidance — so companies can apply ISO 14083 without building their own emission factor libraries from scratch.
The GLEC Framework rates data quality on a 1-to-4 scale. For example, Tier 1 uses actual measured data (GPS distance, fuel meter readings, verified weights). In contrast, Tier 4 uses global average defaults. As a result, CSRD assurance reviewers expect companies to progress toward Tier 1–2 over time, as Tier 4 data may not survive reasonable assurance review.
A GLEC Declaration is a standardised carbon receipt that a transport operator issues to customers, documenting the emissions for their shipment. Specifically, it states the total CO₂e, the data quality tier used, and the calculation methodology — making it directly usable in CSRD Scope 3 disclosures.
Yes. Furthermore, the European Commission recognises it in CSRD guidance as an acceptable methodology for Scope 3 transport emissions reporting. CDP also explicitly recommends it for logistics emissions disclosure.
Specifically, the GLEC Framework covers road, rail, maritime, inland waterways, air (including belly cargo in passenger aircraft), pipelines, cable cars, and logistics nodes such as warehouses, terminals, and distribution centres.