Read your welding certificate — the designation field by field
What the abbreviations mean, and what your test covers
Introduction
A welding certificate does not cover «welding» in general. It covers one combination of process, product, weld type, material, thickness, position and other details. Each part has an abbreviation.
The rule is simple: the certificate is based on a number of essential variables, and for each of them there is a range covered by the test. If you have to weld outside your range, you must take a new test.
The abbreviations
The abbreviations here are from the working draft of the new ISO 9606 (June 2024).
- 01P: plate
- 02T: pipe (also hollow sections)
- 03BW: butt weld
- 04FW: fillet weld
- 05t: the material thickness, i.e. the thickness of the plate or pipe wall
- 06D: outside diameter of the pipe
- 07a: throat thickness, the design thickness of the fillet weld
- 08z: leg length of the fillet weld
- 09S: solid wire or rod
- 10M: metal-cored wire
- 11B: basic covering
- 12R: rutile covering
- 13C: cellulosic covering
- 14nm: no filler material
- 15ss: welded from one side
- 16bs: welded from both sides
- 17mb: with backing (material backing)
- 18nb: without backing (no backing)
- 19sl: single layer
- 20ml: multi-layer
An example
The blacksmith training regulations have the AMU objective «Lys b svejs-stumps plade pos PA-PF». Here the welds are written as «BW-P-PA, 2-n strenge» and «BW-P-PF, 2-n strenge». The first means: butt weld (BW) in plate (P), welded in the flat position (PA), with two or more runs.
A full designation on a certificate has more fields, e.g. material group and thickness. How much your test covers — e.g. how thick plates or which positions — is in tables in the standard. The standard is paid for, so ask your examiner or welding coordinator.
What changes?
The new ISO 9606 is to combine parts 1-5 (steel, aluminium, copper, nickel and titanium) into one standard. In the 2024 working draft the groups have new names, e.g. FE1-FE5 for steel and AL1-AL5 for aluminium. As of October 2026 the standard is still a draft (ISO/DIS 9606, stage 40.60 at ISO), and it does not apply yet.
Keep the certificate alive
Every 6 months, the person responsible for the welding work, the examiner or the certification body must confirm that you have welded within your range. Otherwise the certificate lapses. On issue, one of three routes is chosen: a) a new test every 3 years, b) testing of two welds every 2 years or c) no end date, as long as you stay with the same company and it has a quality system according to ISO 3834-2 or -3. If you want to change route later, it requires a new test.