{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.methane","code":"thing-q37129","url":"https://ver.cy/models/thing/q37129/","name":"methane","alternateNames":["liquid methane","Green methane","dissolved methane","atmospheric methane"],"kind":"thing","status":"published","version":"0.1.0-research.1","language":"en","classifiers":{"family":"Thing Registry","category":"Physical world and living systems","entryKind":"thing","plane":"PHY","domain":["PHY.MAT"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"This model owns methane as the chemical substance CH4, including identified quantities and methane constituents of mixtures, their physical state, composition context, transformation potential and movement between reservoirs.","purpose":"Enable an AI agent to recognise methane, assess its physical and chemical state in context, and determine which handling, use, containment or monitoring actions require further evidence.","scope":{"in":["Chemical identification of methane and evidence distinguishing it from other gases","Methane quantity, concentration, purity and relevant impurities","Physical phase and thermodynamic conditions of an identified methane quantity","Conditions affecting methane release, combustion and oxygen displacement","Methane origin, transformations and transfers between containing systems or environmental reservoirs"],"out":["Natural gas, biogas and other fuel mixtures as complete products","Design, certification and operation of tanks, pipelines, detectors and ventilation systems","Microbial communities and geological formations that generate or consume methane","Combustion appliances, engines and industrial conversion processes as systems","Atmospheric climate models, emissions inventories and carbon accounting methodologies"],"boundaries":[]},"distinguishingFeatures":["An identity-specific analytical result supports CH4 rather than merely reporting a combustible gas; a broad gas alarm alone does not establish methane identity.","Molecular composition establishes one carbon atom and four hydrogen atoms per molecule, distinguishing methane from ethane, propane and other hydrocarbons.","Composition evidence distinguishes methane itself from natural gas or biogas, where methane is one constituent of a mixture.","Odour is not an identity test: pure methane is odourless, while supplied methane-containing gas may contain added odorants.","Biogenic, fossil-derived and synthetic methane share the same molecular identity; their origin requires provenance or suitable analytical evidence."],"structure":{"bundles":[{"id":"methane-identity-and-composition","name":"Methane identity and composition","description":"Establishes whether the material is methane and how methane relates to the sampled mixture.","layers":[{"id":"molecular-identification","name":"Molecular identification","description":"Records evidence supporting assignment to CH4.","findings":[{"id":"methane-specific-evidence","name":"Methane-specific evidence","description":"Separates confirmed methane identity from an indication that could include other gases.","questions":[{"text":"What analytical evidence identifies CH4, and which plausible interfering substances does the method distinguish?","id":"methane-specific-evidence-q01","kind":"definition"},{"text":"Which sample, instrument, calibration and observation time support this identification?","id":"methane-specific-evidence-q02","kind":"provenance"}]}]},{"id":"purity-and-mixture-context","name":"Purity and mixture context","description":"Distinguishes a methane substance quantity from methane contained in a broader material.","findings":[{"id":"methane-fraction-and-companions","name":"Methane fraction and accompanying substances","description":"Records methane abundance and other constituents needed to interpret the sample.","questions":[{"text":"What is the methane fraction, with what uncertainty, reporting basis and wet or dry convention?","id":"methane-fraction-and-companions-q01","kind":"measurement"},{"text":"Is the object being described a methane quantity or a mixture such as natural gas or biogas that needs its own linked model?","id":"methane-fraction-and-companions-q02","kind":"boundary"}]}]}]},{"id":"methane-state-and-inventory","name":"Methane state and inventory","description":"Describes how much methane is present and the conditions under which it exists.","layers":[{"id":"phase-and-host-association","name":"Phase and host association","description":"Records methane phase separately from dissolution, adsorption or hydrate association.","findings":[{"id":"observed-methane-occurrence","name":"Observed methane occurrence","description":"Connects physical occurrence to measured conditions and any host material.","questions":[{"text":"At the recorded temperature, pressure and composition, which methane phases or host associations are observed or inferred?","id":"observed-methane-occurrence-q01","kind":"measurement"},{"text":"Is methane free, dissolved, adsorbed or hydrate-associated, and which host-material model describes its retention?","id":"observed-methane-occurrence-q02","kind":"boundary"}]}]},{"id":"amount-and-volume-basis","name":"Amount and volume basis","description":"Makes methane inventories comparable across conditions.","findings":[{"id":"bounded-methane-inventory","name":"Bounded methane inventory","description":"Defines an amount within an explicit spatial and temporal boundary.","questions":[{"text":"How much methane lies within the stated boundary at the observation time, and what measurement or estimation supports that amount?","id":"bounded-methane-inventory-q01","kind":"measurement"},{"text":"If quantity is reported as gas volume, what temperature, absolute pressure and compressibility treatment define that volume?","id":"bounded-methane-inventory-q02","kind":"measurement"}]}]}]},{"id":"methane-action-conditions","name":"Methane action conditions","description":"Records methane-specific conditions that constrain handling and use.","layers":[{"id":"combustible-atmosphere-context","name":"Combustible atmosphere context","description":"Relates methane concentration to oxidant availability and the surrounding conditions.","findings":[{"id":"ignition-assessment-evidence","name":"Ignition assessment evidence","description":"Collects the contextual evidence needed for an applicable combustible-atmosphere assessment.","questions":[{"text":"What methane and oxygen concentrations, diluents, temperature and pressure characterize the atmosphere being assessed?","id":"ignition-assessment-evidence-q01","kind":"measurement"},{"text":"Which validated criteria apply to these conditions, and what missing evidence prevents authorizing the proposed action?","id":"ignition-assessment-evidence-q02","kind":"action"}]}]},{"id":"release-and-exposure-context","name":"Release and exposure context","description":"Connects methane occurrence to oxygen displacement, pressure release and cold-material exposure where relevant.","findings":[{"id":"handling-constraints","name":"Handling constraints","description":"Records conditions that a linked operating or safety model must resolve before handling.","questions":[{"text":"Could the identified methane quantity enter an occupied or confined space, and what observations establish oxygen availability and accumulation?","id":"handling-constraints-q01","kind":"boundary"},{"text":"What pressure, temperature and release conditions must the linked equipment and operating models address before transfer or phase change?","id":"handling-constraints-q02","kind":"action"}]}]}]},{"id":"methane-origin-and-transformation","name":"Methane origin and transformation","description":"Distinguishes methane formation history from reactions that consume or produce it.","layers":[{"id":"formation-attribution","name":"Formation attribution","description":"Preserves evidence and competing explanations for methane origin.","findings":[{"id":"supported-origin-claim","name":"Supported origin claim","description":"Connects origin labels to supply records, formation context or analytical evidence.","questions":[{"text":"What records, isotopic measurements or associated-gas evidence support the proposed methane origin?","id":"supported-origin-claim-q01","kind":"provenance"},{"text":"Could source mixing or subsequent transformation explain the same evidence, leaving origin unresolved?","id":"supported-origin-claim-q02","kind":"boundary"}]}]},{"id":"chemical-and-biological-conversion","name":"Chemical and biological conversion","description":"Records methane production or consumption through a linked process.","findings":[{"id":"methane-conversion-account","name":"Methane conversion account","description":"Separates methane conversion from phase change, dilution and transfer.","questions":[{"text":"Which process produces or consumes methane, and what reactant, product or rate evidence supports that interpretation?","id":"methane-conversion-account-q01","kind":"measurement"},{"text":"For a proposed conversion, what methane composition and state must the process model accept before the material can be used?","id":"methane-conversion-account-q02","kind":"action"}]}]}]},{"id":"methane-movement-and-environmental-fate","name":"Methane movement and environmental fate","description":"Tracks methane across containment and environmental boundaries.","layers":[{"id":"containment-and-transfer","name":"Containment and transfer","description":"Distinguishes intended methane movement from unintended escape.","findings":[{"id":"methane-boundary-crossing","name":"Methane boundary crossing","description":"Records the source, destination, timing and quantity of a methane transfer.","questions":[{"text":"Across which boundary is methane moving, and is the movement an intended transfer, vent, leak or unresolved event?","id":"methane-boundary-crossing-q01","kind":"boundary"},{"text":"What methane-specific flow measurement or estimation establishes the transferred quantity and its uncertainty?","id":"methane-boundary-crossing-q02","kind":"measurement"}]}]},{"id":"environmental-observation","name":"Environmental observation","description":"Connects methane measurements to reservoirs and possible transport or consumption pathways.","findings":[{"id":"concentration-versus-emission","name":"Concentration versus emission","description":"Separates observed methane abundance from inferred source strength and eventual fate.","questions":[{"text":"Does the evidence describe a local concentration, reservoir inventory or flux, and what sampling extent and interval does it represent?","id":"concentration-versus-emission-q01","kind":"measurement"},{"text":"What transport and methane-consumption evidence is required to connect this observation to a source or an atmospheric release?","id":"concentration-versus-emission-q02","kind":"boundary"}]}]}]}]},"agentConduct":{"may":["Measure and report methane concentrations and leaks with calibrated instruments.","Shut off gas supply or ventilate a space only within an authorized safety plan that prevents ignition and does not require unsafe entry or exposure.","Initiate urgent protective evacuation under applicable emergency policy without waiting for human approval."],"mustNot":["Ignore or delay reporting a methane leak in a building, mine or plant.","Bring an ignition source into an area where methane may have accumulated.","Enter a suspected hazardous atmosphere or operate equipment that could ignite it to provide ventilation or shut off supply.","Delay urgent protective evacuation while awaiting human approval.","Vent methane to the atmosphere when capture or flaring is required.","Understate methane emissions in inventories or reports."],"requiresHuman":["Determining that an affected area is safe for re-entry after a suspected gas leak.","Restarting gas supply after a leak has been repaired."]},"ethics":{"considerations":["Methane leaks cause explosions that kill residents and miners.","Methane is a strong greenhouse gas, and hidden emissions shift harm to everyone."],"affectedParties":["Residents and workers near gas","Miners","Future generations"]},"owners":{"steward":"The operator of the installation or supply that holds it; environmental regulators oversee emissions.","roles":[],"masterSystems":["Greenhouse gas emission inventories","Gas network operator records"]},"relations":[{"target":"Q109910560","type":"parent","note":"registry parent class"},{"target":"Q27105731","type":"parent","note":"registry parent class"},{"target":"Q41581","type":"parent","note":"registry parent class"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.methane","Wikidata: Q37129 (https://www.wikidata.org/wiki/Q37129)"]},"properties":{"applicability":"required","items":["Chemical identity evidence: CH4 confirmed | methane indicated | identity unresolved; include analytical method","Methane quantity: mol or kg; volume only with temperature, pressure and reference basis","Methane fraction: mol/mol, volume fraction or mass fraction; explicitly identify basis and wet or dry reporting","Accompanying substances: Identified mixture constituents and measured fractions, including oxygen, water, carbon dioxide, other hydrocarbons and odorants where relevant","Physical occurrence: Gas | liquid | solid | supercritical fluid | dissolved | adsorbed | hydrate-associated; multiple states may coexist","Temperature and pressure: K or degrees Celsius; Pa or bar with absolute or gauge basis stated","Host or containing system: Linked vessel, pipeline, pore space, water body, sediment, atmosphere or other identified host","Origin attribution: Biogenic | thermogenic | other abiotic | synthetic | mixed | unresolved; retain supporting evidence","Methane transfer rate: kg/s or mol/s across a named boundary over a stated interval"]},"recognition":{"applicability":"required","items":["Instrumental identification is necessary because methane has no visible color under ordinary conditions.","A container label naming methane and stating CH4 provides an identification cue that requires verification against the contents.","Transport markings UN 1971 and UN 1972 distinguish declared compressed methane and refrigerated liquid methane consignments respectively."]},"capabilities":{"applicability":"required","items":["Identify and quantify methane using methods appropriate to the sample matrix and concentration range.","Track methane through storage, transport, dissolution, adsorption and release across named boundaries.","Assess whether evidence supports a proposed containment, transfer or phase-change action under applicable operating constraints.","Evaluate methane as an input to combustion or chemical conversion by linking its composition and state to a process model.","Detect and investigate methane accumulation or loss, retaining measurement uncertainty and sampling context.","Attribute methane origin or environmental fate while preserving unresolved alternatives."]},"hazards":{"applicability":"required","items":["Methane mixed with air can create a fire or explosion hazard.","Accumulation can displace oxygen and create an asphyxiation hazard.","Compressed or refrigerated methane presents pressure hazards, and refrigerated liquid can cause severe cold injury.","Uncontained emissions contribute to climate warming."]},"interfaces":{"applicability":"required","items":["The Globally Harmonized System of Classification and Labelling of Chemicals, published by the United Nations, provides criteria for communicating methane's chemical hazards.","The United Nations Recommendations on the Transport of Dangerous Goods classify compressed methane as UN 1971 and refrigerated liquid methane as UN 1972."]},"context":{"applicability":"required","items":["Methane is the main constituent of natural gas and is used as a fuel and chemical feedstock.","It also occurs in biogas, geological deposits and emissions from wetlands, agriculture and waste decomposition.","Monitoring concerns include fuel quality, leak detection, confined-space safety and greenhouse gas emissions."]}},"sources":[{"title":"Wikidata item Q37129: methane","url":"https://www.wikidata.org/wiki/Q37129","note":"identity and sense of the item"},{"title":"Wikipedia: Methane","url":"https://en.wikipedia.org/wiki/Methane","note":"general description of the item"}],"openQuestions":["Which methane identification and quantification methods should be accepted for each sample matrix, concentration range and interference profile?","Which authoritative phase-property references and mixture models should support state and inventory calculations?","Which jurisdictional and operational criteria should linked safety models apply to particular methane atmospheres and handling actions?","How should isotopically labelled methane be represented without duplicating the registry's methane identity?","What evidence and uncertainty rules are required to support origin attribution and conversion of environmental observations into methane emission estimates?"],"resources":{"spec":"/models/things/publications/thing-q37129/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q37129/spec.json"],"providers":["Codex"],"researchStatus":"unreviewed","generatedAt":"2026-09-07T09:16:37Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"filled","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T12:16:32+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass"},"score":1.0}}