TRA and ETRTO tyre & rim standards publications

• Source / publisher: The Tire and Rim Association, Inc. (us-tra.org — North American standard) and the European Tyre and Rim Technical Organisation (etrto.org — European standard); Japan counterpart JATMA
• Type: standard (dimensional/load/inflation standards manuals)
• Topics: tyre size designations, load ratings & load indices, approved rim contours and valves, rim dimensions, inflation-pressure tables, interchangeability rules for tyre/rim/valve
• Vehicle scope: all (passenger, commercial, agri, OTR, industrial, cycle)
• Region: global (TRA = Americas convention, ETRTO = Europe; JATMA Japan)
• Language: en (ETRTO also publishes fr/de sections)
• Link: etrto.org (2026 SM part catalogue) + etrto.org (booked ~175 EUR) ; us-tra.org (2026 Year Book + Engineering Design Information, digital single-/five-user licences)
• License/access: purchase (copyrighted standards; no free full text — the OEM databooks in this library (Michelin, Bridgestone, Continental, Goodyear) embed the operative tables for truck sizes)
• Notes: the "source of truth" behind every published load/inflation figure. When quoting a standard, cite "ETRTO SM <year>" or "TRA Year Book <year>" — licensing forbids redistribution of the full text.