Sustainability Ontology
A machine-readable ontology for environmental and ESG data: 193 formally defined terms across 6 domains, giving every data element a precise, shared meaning. Semantics defined using The Open Group's O-DEF (Open Data Element Framework).
Three Semantic Axes
Every concept in the ontology is classified along three axes, so each term carries an unambiguous, machine-readable meaning.
Object Classes
What the data element represents (e.g., Resource, Process, Indicator, Ledger)
Roles
The relationship or function of the data element (e.g., Emitter, Trader, Auditor)
Properties
The measurable attribute (e.g., Measure, Amount, Factor, Rating, Identifier)
Semantic Codes
Each ontology term carries a 3-axis semantic code. Codes are assigned using O-DEF™ (Open Data Element Framework), The Open Group standard we used to define the semantics.
Example:
ofp-sustainability:3.1~1.1_5.1Resource.Emission-Source ~ Trader.Emitter _ Measure.Emission-Measure
Domain Coverage
Ontology Browser
Search and filter across 30 representative terms.
Emission Quantity
GHGmeasurementTotal GHG emission quantity for a given activity, period, and scope (kgCO2e, tCO2e).
3.1~1.1_5.1Emission Factor
GHGmeasurementConversion factor from activity data to GHG emissions (e.g., kg CO2e per unit).
3.1~1.1_5.2Emission Scope
GHGclassificationGHG Protocol classification: Scope 1 (direct), Scope 2 (energy indirect), Scope 3 (value chain).
Emission Source
GHGclassificationPhysical source or activity that produces GHG emissions (e.g., combustion, process, fugitive).
Global Warming Potential
GHGmeasurementGWP conversion factor for non-CO2 gases relative to CO2 over a specified time horizon.
Carbon Intensity
GHGindicatorEmissions per unit of output (gCO2e/MJ, kgCO2e/MWh, etc.).
Activity Data
GHGmeasurementQuantitative measure of an activity that causes GHG emissions (fuel consumed, distance traveled, etc.).
Gas Type
GHGclassificationSpecific greenhouse gas (CO2, CH4, N2O, HFCs, PFCs, SF6, NF3).
Reporting Period
GHGtemporalTime period for which emissions are calculated and reported.
Verification Status
GHGverificationCurrent verification state of an emission record (Pending, Approved, Non-Conformance).
Water Withdrawal Volume
WatermeasurementTotal volume of water withdrawn from all sources.
Water Discharge Volume
WatermeasurementTotal volume of wastewater discharged.
Water Source Type
WaterclassificationClassification of water source (surface, ground, municipal, recycled, etc.).
Habitat Area
BiodiversitymeasurementArea of natural habitat affected by operations.
Species Impact
BiodiversityindicatorImpact assessment on endangered or protected species.
Workforce Count
SocialmeasurementNumber of employees and contractors.
Safety Incident Rate
SocialindicatorFrequency of workplace safety incidents.
Diversity Ratio
SocialindicatorProportion of underrepresented groups in workforce.
Board Independence
GovernanceindicatorProportion of independent directors on the board.
Compliance Status
GovernanceclassificationRegulatory compliance assessment status.
Organization ID
Cross-DomainidentificationUnique identifier for a reporting organization.
Facility ID
Cross-DomainidentificationUnique identifier for a facility where emissions occur.
Data Quality Score
Cross-Domaindata_qualityOverall data quality assessment on the PACT 1-5 scale.
E-Ledger Balance
Cross-DomainledgerCurrent balance of an E-Ledger (total debits minus total credits in kgCO2e).
3.4~1.1_7.2E-Ledger Transfer
Cross-DomainledgerCarbon liability transfer between E-Ledgers in the supply chain.
9.2~2.1_7.2Carbon Credit
Cross-DomainledgerCircular economy credit from material recycling or carbon offsets.
9.2~2.1_7.3Allocation Weight
Cross-DomainrecordingPercentage weight for distributing shared emissions to co-products.
Lifecycle Stage
Cross-DomainlifecycleStage in the product lifecycle (raw material, production, use, end-of-life).
Assurance Level
Cross-DomainreportingLevel of external assurance for reported data (limited, reasonable).
Geographic Coordinates
Cross-DomainspatialLatitude/longitude of emission source or facility.
Semantic Grounding Chain
Every data element in the Open Footprint standard is annotated with a 3-axis semantic code (defined using O-DEF) that grounds it in the ontology, ensuring semantic interoperability across implementations.