{"closest_prior_art":[{"name":"DOE HyBlend pipeline-material compatibility program","overlap":"Tests pipeline materials at varying hydrogen concentrations and pressures up to 100 bar to determine susceptibility and inform blend limits based on pipeline design and condition.","remaining_difference":"The source does not describe removable precracked sentinels, methane-rich parallel controls, step-down persistence testing, repeated destructive retrieval, or segment-specific operating gates.","source_ids":["SRC1"]},{"name":"NIST pressurized-hydrogen fatigue testing of pipeline welds and heat-affected zones","overlap":"Measures fatigue-crack-growth behavior of API X52 and X70 base, weld, and heat-affected-zone specimens in pressurized hydrogen and examines pressure, residual-stress, and crack-path effects.","remaining_difference":"It is a laboratory characterization program rather than a longitudinal sentinel system integrating step-up/step-down exposure, retained-damage measurements, material provenance, and transition decisions.","source_ids":["SRC2"]},{"name":"SGN/ENA full-scale cyclic-hydrogen crack monitoring project","overlap":"Uses vintage pipeline material, a manufactured internal defect, cyclic gaseous hydrogen, continuous ultrasonic monitoring, and multiple pressure observations to track progressive crack development.","remaining_difference":"It uses a full-scale fatigue vessel rather than removable precracked coupons and does not report a methane control, step-down/purge/retest sequence, residual-toughness retrieval, or segment decision mapping.","source_ids":["SRC3"]},{"name":"ASME B31.12 Hydrogen Piping and Pipelines","overlap":"Establishes recognized requirements for hydrogen-pipeline materials, design, testing, inspection, operation, and maintenance.","remaining_difference":"It supplies the governing engineering framework, not the proposed co-exposure sentinel architecture or its contrastive decision experiment.","source_ids":["SRC4"]}],"contrastive_claim_falsifier":"The claim is falsified if blinded sentinel measurements fail to predict the direction or material ranking of crack growth and residual toughness in reserved specimens, if step-down testing shows no reproducible retained-damage or hysteresis signal, or if the sentinel evidence changes no segment classification or authorized transition gate relative to code-based assessment, ordinary inspection, and conventional laboratory testing.","contrastive_claim_remaining":"A distinct claim remains that a combined, material-provenanced sentinel protocol—parallel methane-rich and hydrogen-bearing exposure, precracked specimens, step-up/step-down cycles, destructive residual-property testing, and explicit segment mapping—can reveal thresholds or retained damage that change at least one justified transition tempo, pressure envelope, inspection gate, reinforcement choice, or retirement decision beyond established testing and inspection practices.","experiment_id":"eoa_inverse_innovation_exp13_second_slot_policy60_20260806","gates":{"adequate_source_search":{"rationale":"The bounded search covered the proposal directly, historical and synonymous concepts such as surveillance specimens and hydrogen-embrittlement testing, products/practices/standards, and combinations including vintage material, weld zones, cyclic hydrogen, crack monitoring, and retrievable coupons. Four opened sources span DOE, NIST, ENA/SGN, and ASME.","source_ids":["SRC1","SRC2","SRC3","SRC4"],"status":"PASS"},"bounded_next_test":{"rationale":"Two isolated laboratory cells with blind-matched precracked coupons, a methane-rich control, bounded step-up/step-down cycles, destructive testing, and reserved independent-validation specimens are technically aligned with established pressurized-hydrogen materials testing while avoiding an operating pipeline.","source_ids":["SRC1","SRC2","SRC4"],"status":"PASS"},"distinct_testable_claim":{"rationale":"Prior art establishes variable-concentration material testing, weld/HAZ crack-growth testing, and full-scale cyclic-hydrogen monitoring, but the remaining claim requires a measurable improvement in material ranking or a changed segment decision from the combined sentinel protocol.","source_ids":["SRC1","SRC2","SRC3"],"status":"PASS"},"no_obvious_safety_or_authority_stop":{"rationale":"High-pressure hydrogen presents serious pressure, leakage, ignition, and embrittlement hazards, but the authorized first experiment is confined to isolated laboratory equipment under process-safety control and does not alter live service. Any pipeline application remains subject to operator, regulator, asset-owner, and applicable-code approval.","source_ids":["SRC1","SRC4"],"status":"PASS"},"supported_problem":{"rationale":"DOE states that blend limits depend on pipeline-material design and condition; NIST found relevant differences among pipeline welds, heat-affected zones, and base metal under pressurized hydrogen; and the SGN project observed progressive crack development plus measurement complications from material inhomogeneity.","source_ids":["SRC1","SRC2","SRC3"],"status":"PASS"}},"prior_art_disposition":"ADJACENT_PRIOR_ART","problem_evidence":{"finding":"The engineering problem is visible: hydrogen blend limits are material- and condition-dependent, weld and heat-affected-zone fatigue behavior must be characterized in pressurized hydrogen, and cyclic testing of vintage pipe can reveal progressive crack growth whose measurement is affected by material inhomogeneity. The sources do not establish that fleet-level indicators alone reliably expose these local regimes.","source_ids":["SRC1","SRC2","SRC3"],"status":"SUPPORTED"},"research_id":"eoa_inverse_innovation_exp13_light_screen_20260806","schema_version":1,"screen_id":"E13P089","screen_survival":true,"search_lanes":{"component_combination":{"no_result_note":null,"queries":["hydrogen pipeline in situ coupon exposure loop fracture toughness crack growth","hydrogen pipeline step-up step-down exposure retained damage fracture toughness coupon","hydrogen embrittlement coupon holder bypass pipeline monitoring","hydrogen pipeline coupon monitoring product sensor crack growth"],"source_ids":["SRC1","SRC2","SRC3"]},"direct_problem_and_intervention":{"no_result_note":null,"queries":["hydrogen pipeline sidestream coupon exposure precracked sentinel bypass materials monitoring","hydrogen gas pipeline in situ coupon exposure loop fracture toughness crack growth","pipeline hydrogen material coupon surveillance bypass loop","hydrogen pipeline surveillance specimens coupons service exposure monitoring"],"source_ids":["SRC1","SRC2","SRC3"]},"products_practices_and_standards":{"no_result_note":null,"queries":["ASME B31.12 material testing fatigue crack growth hydrogen pipeline conversion existing","ASTM standard gaseous hydrogen embrittlement pipeline steel fracture toughness fatigue crack growth","hydrogen pipeline corrosion coupon retrievable sidestream cell crack growth monitoring","hydrogen pipeline coupon monitoring product sensor crack growth"],"source_ids":["SRC3","SRC4"]},"synonyms_and_historical_terms":{"no_result_note":null,"queries":["surveillance program hydrogen pipeline coupons","hydrogen embrittlement coupon holder bypass pipeline monitoring","hydrogen pipeline corrosion coupon retrievable sidestream cell crack growth monitoring","ASME B31.12 existing pipeline conversion hydrogen fracture toughness testing requirements"],"source_ids":["SRC2","SRC4"]}},"sources":[{"claims_supported":["Hydrogen blend limits depend on the design and condition of pipeline materials and infrastructure.","DOE's HyBlend program tests pipeline materials at varying hydrogen concentrations and pressures up to 100 bar.","Materials-compatibility testing and structural-integrity tools are established parts of hydrogen-pipeline transition research."],"publisher":"U.S. Department of Energy","source_id":"SRC1","source_type":"OFFICIAL_GUIDANCE","title":"HyBlend: Opportunities for Hydrogen Blending in Natural Gas Pipelines","url":"https://www.energy.gov/cmei/fuels/hyblend-opportunities-hydrogen-blending-natural-gas-pipelines"},{"claims_supported":["API X52 and X70 pipe welds and heat-affected zones have been tested for fatigue crack growth in pressurized hydrogen gas.","Susceptibility comparisons consider residual stress, crack path, and hydrogen-pressure effects."],"publisher":"National Institute of Standards and Technology","source_id":"SRC2","source_type":"PRIMARY_RESEARCH","title":"Fatigue Testing of Pipeline Welds and Heat-Affected Zones in Pressurized Hydrogen Gas","url":"https://www.nist.gov/publications/fatigue-testing-pipeline-welds-and-heat-affected-zones-pressurized-hydrogen-gas"},{"claims_supported":["A completed project cyclically tested a vintage X52 pipeline specimen with a manufactured internal defect in gaseous hydrogen.","Continuous time-of-flight-diffraction monitoring detected progressive crack development before vessel failure at approximately 12,000 cycles.","Material inhomogeneity and inspection geometry complicated crack-path interpretation."],"publisher":"Energy Networks Association / SGN","source_id":"SRC3","source_type":"PRIMARY_RESEARCH","title":"NDT Fatigue crack growth rate of hydrogen pipelines","url":"https://smarter.energynetworks.org/projects/nia2_sgn0065/"},{"claims_supported":["ASME B31.12 applies to gaseous-hydrogen and hydrogen-mixture pipelines.","The code addresses materials, design, testing, inspection, operation, and maintenance and is intended for operators, owners, inspectors, manufacturers, and governing entities."],"publisher":"American Society of Mechanical Engineers","source_id":"SRC4","source_type":"OFFICIAL_STANDARD","title":"B31.12 - Hydrogen Piping and Pipelines","url":"https://www.asme.org/codes-standards/find-codes-standards/hydrogen-piping-and-pipelines"}],"world_novelty_boundary":"This bounded public-web screen found substantial adjacent work on hydrogen-exposed pipeline specimens, weld/HAZ fatigue testing, full-scale cyclic-hydrogen crack monitoring, and applicable pipeline standards, but no retained source describing the complete proposed combination. That phrase and combination miss does not establish world novelty, patentability, market size, expert acceptance, or realized value."}