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Can I use a PQR qualified to an old or superseded standard?


Frequently asked questions

According to the two most commonly applied standards for welding procedure qualification: ASME IX and the EN ISO 15614 series, existing and 'old' procedure qualification can be used, provided some specific requirements are met. These are summarised below:

ASME IX provides requirements on the use of existing PQRs in QW-100.3:

  • PQRs carried out according to the 1962 Edition of ASME IX or later can be used for any construction built to the ASME Boiler and Pressure vessel code or the ASME B31 code.
  • PQRs carried out to editions of ASME IX prior to 1962 can be used provide all requirements of the 1962 or later editions are met.
  • If an 'old' PQR is used, records that document the essential variable required by the current edition of the code must be available.
  • In practice, the validity of a PQR to ASME IX is unlimited, except when impact testing is required.

EN ISO 15614 includes in its introduction requirements for the use of procedures qualified to its predecessor EN 288 or other national standards, in summary:

  • EN ISO 15614 does not invalidate previous welding procedure tests made to former national standards or specifications or previous issues of this standard.
  • Existing qualifications that are correctly documented can be made technically equivalent to the current edition of ISO 15614, in this case it is only necessary to carry out any additional tests on a test piece which should be made in accordance ISO 15614.


TWI is not authorised to give official interpretations of BS EN ISO and ASME Standards. This answer is an opinion only, and cannot be taken as a definitive answer. No liability rests with TWI for any damages arising from this answer.

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