Ways to make Oxygen

2 routes in the Atlas, side by side per the same functional unit. Whether they compare is computed from their data, criterion by criterion; a warning sits next to each route it concerns.

Not comparable as they standFunctional unit: differs; Reference product (grade, state): differs. The rows say which route each warning concerns.

Per 1 t of Oxygen: inventory from each route's LCI dataset, unallocated; footprints per the functional unit of their own LCA.

Route	Tier, design maturity, review status	Geography, year	Energy	Feedstocks	Key emissions	Footprint	Comparability
Cryogenic air separation unit (500 t/d GOX)cryogenic double-column air separation, 500 t/d GOX, pumped liquid products, TSA front endoxygen/gox-30barg-99.5	flowsheet or hand-writtenDesign maturity: Screening (research)Not independently reviewedDataset review: not stated	generic, 2026	Electric power (6.6 kV grid supply): 502 kWh	Ambient air: 5,433 kg (free) Molecular sieve 13X and activated alumina (V-2101A/B): 0.0342 kg Lubricating oil (K-1101, K-4101, K-4102, K-3101): 0.0114 kg	none	66.7 kg CO2-eq33.1 to 133 (95 %)Climate change per 1 t oxygen, gaseous, >= 99.5 mol%, 30 barg	Reference product (grade, state): product is oxygen/gox-30barg-99.5 (basis mole, component O2, phase gas, pressure 31.0, purity 0.997115, temperature 40.0); the routes state oxygen/gox-30barg-99.5 (basis mole, component O2, phase gas, pressure 31.0, purity 0.997115, temperature 40.0), oxygen/lox (basis mole, component O2, phase liquid, pressure 1.3, purity 0.998093, temperature -183.0) Functional unit: functional unit is 1 t; the routes state 1 kg, 1 t
Cryogenic air separation unit (500 t/d GOX)cryogenic double-column air separation, 500 t/d GOX, pumped liquid products, TSA front endoxygen/lox	flowsheet or hand-writtenDesign maturity: Screening (research)Not independently reviewedDataset review: not stated	generic, 2026	a co-product of a multi-output dataset (product:GOXP, product:GANP, product:LIN besides it): its share needs the allocation of the LCI database build			no footprint	Reference product (grade, state): product is oxygen/lox (basis mole, component O2, phase liquid, pressure 1.3, purity 0.998093, temperature -183.0); the routes state oxygen/gox-30barg-99.5 (basis mole, component O2, phase gas, pressure 31.0, purity 0.997115, temperature 40.0), oxygen/lox (basis mole, component O2, phase liquid, pressure 1.3, purity 0.998093, temperature -183.0) Functional unit: functional unit is 1 kg; the routes state 1 kg, 1 t

Footprint data: UK Government GHG Conversion Factors for Company Reporting 2026 (flat file) (OGL-3.0); Greenhouse gas emission intensity of electricity generation in Europe (indicator ENER038) (CC BY (version not stated) under the EEA legal notice (https://www.eea.europa.eu/en/legal-notice): re-use, including commercial, with the EEA acknowledged in each copy and the meaning not distorted). Contains public sector information licensed under the Open Government Licence v3.0 (UK Government GHG Conversion Factors for Company Reporting 2026, DESNZ). Source: European Environment Agency (EEA), indicator ENER038 'Greenhouse gas emission intensity of electricity generation in Europe' (2026), https://www.eea.europa.eu/en/analysis/indicators/greenhouse-gas-emission-intensity-of-1, CC BY; values converted from g to kg CO2e per kWh.

How comparability is checked

Allocation: same (same allocation method: exergy)
Background data (impacts): not applicable (same background data and boundary behind the impact numbers (only routes with a footprint))
System boundary: same (same system boundary of the inventory (the dataset's boundary): gate-to-gate foreground of the plant with its construction)
Data quality (TfS DQR): same (data quality: every route states a TfS DQR, none more than 1 above the best)
Functional unit: differs (same functional unit (amount and unit of the reference product): 1 kg, 1 t)
Reference product (grade, state): differs (same reference product: registry grade and state: oxygen/gox-30barg-99.5 (basis mole, component O2, phase gas, pressure 31.0, purity 0.997115, temperature 40.0), oxygen/lox (basis mole, component O2, phase liquid, pressure 1.3, purity 0.998093, temperature -183.0))
System model: same (same system model (docs/system-model.md): cutoff)

Market activity in the LCI database: market:oxygen/lox:RER (production-mix, RER), market:oxygen/gox-30barg-99.5:RER (production-mix, RER). Link a consumer of Oxygen to the market rather than to one route.

ISO 14044 requires a critical review (by a panel of interested parties, ISO/TS 14071) of a comparative assertion intended to be disclosed to the public. These routes are listed side by side for screening; a statement that one is better than another needs that review. None of these routes has had such a review.