Certification of welding processes

EN ISO 3834

Certification of your company in accordance with the EN ISO 3834 series of standards declares the assessment of the manufacturer's competence and is internationally recognized proof of its ability to ensure welding quality.

The EN ISO 3834 series of standards define the manufacturer's quality requirements and the principles that ensure the quality of welded products.

Certification of your welding activities by the experts of OTC Bulgaria Ltd in accordance with EN ISO 3834 brings you the following advantages:

  • Certification is suitable for all companies working in the field of welding processes - for serial production, individual production, repair or assembly activities;
  • Increase your competitiveness through proven high quality of your products;
  • Optimize your processes;
  • Reduce costs;
  • Choose a partner with a proven presence in the certification market.

How the certification process is carried out

The initial certification, which is carried out by OTC Bulgaria Ltd, takes place in two stages.

In the first stage the conformity of the documentation is determined according to the requirements of the relevant part of EN ISO 3834.

The on-site audit in the second stage aims to verify how the requirements of the relevant EN ISO 3834 series standard are applied in your company.

If compliance between the requirements and their application in the welding processes is found, we will issue you with a certificate with a validity period of 3 years. In the second and third year, our experts conduct so-called surveillance audits. Their number during the validity period of the certificate depends on the certification level, scope and results of the certification audit.

EN ISO 3834 distinguishes three different welding quality levels: "Comprehensive", "Standard" and "Basic". Our experts will advise you which level is most suitable for your business.

EN ISO 3834-2

"Comprehensive" quality requirements

A Quality Management System (QMS) must be implemented and operational in the company, ISO 9001 certification is recommended;

A Welding Coordinator must be in place who has extensive knowledge in the design, fabrication and testing of welding components, such as having an International Welding Engineer (IWE/EWE) qualification; the responsibilities and duties of this employee and authority must be clearly defined in accordance with EN ISO 14731

Welders should have a valid certificate in accordance with EN ISO 9606/ EN 287-1. Operators for fully mechanised and automatic welding processes must hold a

valid certificate in accordance with EN ISO 14732 /EN 1418. When performing

non-destructive testing, you must have certified inspection personnel in accordance with EN ISO 9712 /EN 473.

EN ISO 3834-3

"Standard" quality requirements

A quality management system is required and an adequately documented and implemented quality manual or alternatively written procedures, work instructions and other specifications must be in place. The interaction of the individual processes shall then be verified.

All other requirements shall comply with EN ISO 3834-2.

EN ISO 3834-4

"Basic" quality requirements

The third level does not require a Quality Management system.

A welding supervisor in terms of EN ISO 14731 is not necessary.

As a manufacturer you have the responsibility for the welding-technical part of the production and therefore, basic knowledge of the quality requirements for the required production monitoring for welding has to be demonstrated. The responsibility can, of course, be transferred to the appropriate persons, and the fulfilment of the required welding-related quality has to be specified in writing.

The welders need a valid certification in accordance with EN 287-1, ISO 9606-2 and with fully mechanized and automatic welding processes, machine operators must have a valid certification in accordance with EN 1418.

Contact us:

Contact us to learn about our certification services and how we can help your company achieve success with management, product, and welding certifications.


+359 2 980 04 18

+ 359 888 13 98 94


Bulgaria, Sofia 1000, 12, Hristo Belchev str.