generated: '2026-09-05' method: searched source: https://geodata.bts.gov/api/search/v1/conformance note: >- Conformance for the Bureau of Transportation Statistics API surface. BTS runs three first-party machine-readable surfaces on hosts it controls: data.bts.gov (Socrata / Tyler Data & Insights SODA 2.1 + OData 4.0 + Project Open Data DCAT-US 1.1), geodata.bts.gov (ArcGIS Hub, OGC API - Records/Features + a first-party OpenAPI 3.0), and www.transtats.bts.gov (HTML query forms, no machine contract). Every entry below carries the exact URL that was fetched on 2026-09-05. Platform-level conformance is labelled as such — the class URIs are served BY BTS's own hosts, but the implementation belongs to the hosting platform (Tyler Data & Insights, Esri ArcGIS Online). standards: - id: ogcapi-common-1 name: OGC API - Common Part 1 Core conforms: true evidence: >- https://geodata.bts.gov/api/search/v1/conformance declares http://www.opengis.net/spec/ogcapi-common-1/1.0/conf/core and .../conf/json file: conformance/bureau-of-transportation-statistics-geodata-conformance.json - id: ogcapi-common-2 name: OGC API - Common Part 2 Collections conforms: true evidence: >- https://geodata.bts.gov/api/search/v1/conformance declares http://www.opengis.net/spec/ogcapi-common-2/0.0/conf/collections and .../conf/json file: conformance/bureau-of-transportation-statistics-geodata-conformance.json - id: ogcapi-features-1 name: OGC API - Features Part 1 Core conforms: true evidence: >- https://geodata.bts.gov/api/search/v1/conformance declares http://www.opengis.net/spec/ogcapi-features-1/1.0/conf/core, .../conf/geojson and .../conf/oas30 file: conformance/bureau-of-transportation-statistics-geodata-conformance.json - id: ogcapi-records-1 name: OGC API - Records Part 1 Core conforms: true domain_standard: true evidence: >- https://geodata.bts.gov/api/search/v1/conformance declares http://www.opengis.net/spec/ogcapi-records-1/1.0/conf/core and .../conf/json; the catalog collection is served at https://geodata.bts.gov/api/search/v1/collections/dataset/items file: conformance/bureau-of-transportation-statistics-geodata-conformance.json - id: odata-v4 name: OASIS OData 4.0 conforms: true domain_standard: true evidence: >- https://data.bts.gov/api/odata/v4/$metadata returns a CSDL/EDMX 4.0 document (edmx:Edmx Version="4.0", OASIS namespace) declaring 184 EntityTypes and 184 EntitySets, one per tabular BTS dataset; a dataset feed at https://data.bts.gov/api/odata/v4/bw6n-ddqk returns @odata.context. HTTP 200, fetched 2026-09-05. file: odata/bureau-of-transportation-statistics-odata-metadata.xml - id: dcat-us-1.1 name: Project Open Data / DCAT-US 1.1 conforms: true domain_standard: true evidence: >- https://data.bts.gov/data.json returns a dcat:Catalog with conformsTo https://project-open-data.cio.gov/v1.1/schema and 418 datasets (HTTP 200); https://geodata.bts.gov/api/feed/dcat-us/1.1.json returns the same shape with 142 NTAD datasets. Required by OMB M-13-13 for federal agencies. - id: dcat-rdf name: DCAT (W3C) RDF/XML serialization conforms: true evidence: >- https://data.bts.gov/api/dcat.rdf returns application/rdf+xml using the http://www.w3.org/ns/dcat# vocabulary (HTTP 200, 925 KB). - id: soda-2.1 name: Socrata Open Data API (SODA) 2.1 conforms: true domain_standard: true evidence: >- https://data.bts.gov/resource/bw6n-ddqk.json?$limit=2 returns HTTP 200 with SoQL parameters honoured; response carries X-Socrata-RequestId and X-Socrata-Region. Documented at https://dev.socrata.com/docs/endpoints.html - id: geoservices-rest name: Esri ArcGIS GeoServices REST Specification conforms: true evidence: >- https://services.arcgis.com/xOi1kZaI0eWDREZv/arcgis/rest/services?f=json returns currentVersion 12 with 1,079 FeatureServer services for the USDOT/BTS ArcGIS Online tenant that backs geodata.bts.gov (HTTP 200). - id: geojson-rfc7946 name: GeoJSON (RFC 7946) conforms: true evidence: >- SODA serves /resource/{id}.geojson; the OGC API - Records surface declares http://www.opengis.net/spec/ogcapi-features-1/1.0/conf/geojson - id: fedramp name: FedRAMP authorized hosting conforms: true operator: platform evidence: >- Live responses from https://data.bts.gov carry X-Socrata-Region: aws-us-east-1-fedramp-prod (observed 2026-09-05). The FedRAMP authorization belongs to the platform operator (Tyler Data & Insights / Socrata), not to BTS; BTS publishes no compliance or trust page of its own, so no Compliance pointer is emitted. - id: oauth2 conforms: false evidence: >- No oauth2 securityScheme in any harvested spec; /.well-known/oauth-authorization-server and /.well-known/openid-configuration 404 on data.bts.gov, geodata.bts.gov and www.transtats.bts.gov. - id: oidc conforms: false evidence: /.well-known/openid-configuration returns 404 on every BTS host probed. - id: rfc9457-problem-details conforms: false evidence: >- Errors use the Socrata envelope {code, error, message, status, data, source} with content-type application/json, not application/problem+json. Observed live at https://data.bts.gov/resource/23mg-e8r7.json (403) and https://data.bts.gov/api/odata/v2/bw6n-ddqk (404). - id: json-api conforms: false evidence: No JSON:API media type or document structure in any surface. - id: pagination conforms: true evidence: >- SODA $limit/$offset (default 1000, max 50000); OGC API - Records limit/startindex on /api/search/v1/collections/{collectionId}/items; OData $top/$skip. See conventions/bureau-of-transportation-statistics-conventions.yml - id: idempotency conforms: false evidence: >- Read-only surface — every operation in every harvested spec is GET, so there is no mutating request to make idempotent.