JIS Z 3104: Radiographic Testing of Welds
Japanese standard for radiographic weld inspection covering procedures and acceptance criteria.
JIS maintains JIS Z 3104 as a published consensus standard used across the NDT industry.
JIS Z 3104 becomes enforceable when invoked by a contract, regulatory citation, or another standard that references it as the controlling document.
JIS Z 3104 is invoked when the scope of work matches its title — radiographic testing of welds — and when the contract or regulatory regime cites it as the controlling document. On petroleum and petrochemical equipment, JIS Z 3104 usually feeds into a written mechanical-integrity program: inspection intervals, examination methods, and acceptance criteria are all traced back to a clause number in the document. In fabrication shops the standard is reproduced inside the written procedure book and referenced from every inspection report so that the auditor's paper trail leads back to the same paragraph the inspector worked from.
Methods covered
Industries
- Construction
- Manufacturing
- Oil & Gas
- Personnel qualification: examinations under JIS Z 3104 must be performed by inspectors qualified and certified to a recognised scheme (typically ASNT SNT-TC-1A, CP-189, or ISO 9712 depending on jurisdiction), with documented training hours, vision tests, and a controlling written practice.
- Written procedure: every examination requires a written, controlled procedure that names the method, equipment, calibration steps, scanning pattern, and acceptance criteria — and is qualified before first use.
- Image-quality verification: every radiograph or digital exposure carries a penetrameter / IQI of the type and thickness specified by the standard; the IQI must be visible and at the required sensitivity for the radiograph to be acceptable.
- Radiation safety: source handling, exclusion zones, dosimetry, and source recordkeeping must follow the licensing authority's rules in addition to the inspection standard itself.
- Acceptance criteria: indications are evaluated against the standard's tabulated limits (length, depth, alignment, frequency); any indication exceeding the criteria is recorded, dispositioned, and either repaired or evaluated for fitness-for-service.
- Documentation: examination reports must include enough information for a third party to reproduce the inspection — equipment serial numbers, calibration records, inspector ID, sketches of indications, and the controlling procedure revision.
JIS Z 3104 is maintained on its publishing organisation's revision cycle. The version cited in any contract or written inspection program should be tracked so that revisions can be reviewed against the existing inspection plan and any clause changes worked into the next procedure update.
A typical refinery turnaround applies JIS Z 3104 to the inspection scope for high-temperature piping and pressure vessels: corrosion-monitoring locations are read with UT thickness gauges, girth welds on repaired sections are radiographed or PAUT-scanned, and any indication outside the standard's acceptance table is dispositioned through API 579 fitness-for-service before the unit restarts.
What does JIS Z 3104 cover?
JIS Z 3104 (Radiographic Testing of Welds) is published by JIS. Japanese standard for radiographic weld inspection covering procedures and acceptance criteria..
Is JIS Z 3104 mandatory or voluntary?
JIS Z 3104 is a consensus standard. It becomes mandatory when invoked by a contract, by another code that cites it (for example ASME Section V calling out an ASTM practice), or by a regulator that has adopted it into law in a specific jurisdiction.
Who is qualified to perform inspections under JIS Z 3104?
Inspections under JIS Z 3104 must be performed by personnel qualified and certified to a recognised NDT certification scheme — most commonly ASNT SNT-TC-1A or CP-189 in the United States, ISO 9712 in much of the rest of the world, and NAS 410 for aerospace work. The written practice that controls qualification must be in place before any examination is started.
Which other standards are commonly cited alongside JIS Z 3104?
JIS Z 3104 is most often cited together with the parent code that brings it into the contract — typically ASME Section V or VIII for U.S. pressure equipment, AWS D1.1 for structural welding, API 510/570/653 for in-service petroleum equipment, or the matching EN/ISO standard for European and international work.
Standard Code
JIS Z 3104
Organization
JIS
Methods Covered
1 method(s)
Industries
3 sector(s)
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