What is EN 1090 Certification?

The EN 1090 standard establishes the benchmark for the fabrication and assembly of steel and aluminum structures within the European Economic Area. It represents a comprehensive system of technical requirements, quality control procedures, and conformity assessment protocols that every structural fabricator must integrate to produce components legally for construction projects across Europe.

EN 1090 directly supports the Construction Products Regulation (CPR) (EU Regulation 305/2011). The CPR mandates that construction products must carry the CE marking to demonstrate they meet harmonized European standards for performance, safety, and environmental protection. Without EN 1090 certification, a fabricator cannot legally affix the CE mark to structural steel or aluminum components. This makes the standard a non-negotiable prerequisite for market access, whether for a multi-story commercial building, an industrial warehouse, or a pedestrian bridge.

The reach of EN 1090 extends beyond the fabricator alone. Importers and distributors are also responsible for ensuring the products they place on the market are compliant. As a result, the standard fosters a chain of accountability that reinforces safety and quality from the design stage through to installation.

The legal obligation underpinning EN 1090 is the CPR. The regulation provides a common technical language for assessing the performance of construction products. For structural steel and aluminum, the System of Assessment and Verification of Constancy of Performance (AVCP) is typically System 2+. This system requires the manufacturer to operate a certified Factory Production Control (FPC) system and to undergo initial type testing of the product. The certification body—known as a Notified Body—must issue the certificate of conformity for the FPC.

It is a legal offense in EU member states to place products covered by a harmonized standard on the market without the appropriate CE marking and supporting documentation. For specifiers, contractors, and clients, specifying EN 1090 compliance is the primary mechanism for managing liability and ensuring the structure meets its intended design life and safety requirements.

Anatomy of the Standard

EN 1090 is not a single document but a series of interrelated parts that define how structures must be executed and assessed.

EN 1090-1: Conformity Assessment

EN 1090-1 outlines the procedures for assessing the conformity of structural components. It defines the responsibilities of the manufacturer and the Notified Body, sets the rules for the CE marking, and establishes the framework for the Factory Production Control (FPC) system. This part is fundamentally about process documentation and governance.

EN 1090-2: Technical Requirements for Steel Structures

This is the most detailed and widely applied part of the standard. EN 1090-2 provides comprehensive technical specifications for the execution of steel structures. It covers material selection, preparation and assembly, welding, mechanical fastening, dimensional tolerances, inspection, testing, and installation. It references hundreds of other European standards (EN, EN ISO) for specifics like welding procedures, non-destructive testing (NDT), and material certification.

EN 1090-3: Technical Requirements for Aluminum Structures

EN 1090-3 mirrors EN 1090-2 but is tailored to the unique properties of aluminum, including its lower melting point, higher thermal conductivity, and specific welding characteristics. The standard addresses the distinct challenges of working with aluminum, such as heat-affected zone softening and the need for specific filler alloys. Fabricators working with both steel and aluminum must achieve certification for both scopes under their EN 1090 system.

Execution Classes (EXC1, EXC2, EXC3, EXC4)

A foundational concept within EN 1090-2 and EN 1090-3 is the Execution Class. This classification system scales the strictness of fabrication and inspection requirements based on the potential consequences of structural failure. The design engineer specifies the required EXC for each element or the entire structure.

  • EXC1 (Low Consequence): Applies to structures with a low risk to life and low economic impact in the event of failure. Typical examples include single-story agricultural buildings or small storage sheds where the loss of structural integrity poses minimal danger. Fabrication requirements are basic.
  • EXC2 (Standard Consequence): This is the default execution class for most commercial and residential buildings. It represents a balanced approach where risk is moderate, and standard fabrication and inspection practices are sufficient. Most structural steelwork in offices, schools, and apartment buildings falls under EXC2.
  • EXC3 (High Consequence): Reserved for structures that carry a high risk to life or significant economic or social disruption if they fail. Examples include stadiums, high-rise buildings, hospitals, and public assembly spaces. EXC3 requires more rigorous welding supervision, more extensive NDT (Non-Destructive Testing), and stricter material traceability.
  • EXC4 (Very High Consequence): The most stringent class, applied to critical infrastructure such as major bridges, nuclear containment buildings, and offshore platforms. EXC4 demands the highest level of quality control, including comprehensive NDT, highly qualified welding coordination personnel, and detailed, audited traceability for all materials and processes.

Core Requirements for Certification

Achieving and maintaining EN 1090 certification demands the integration of several critical technical and managerial systems.

Factory Production Control (FPC)

The FPC system is the engine of continuous compliance. It is a documented set of procedures, work instructions, and records that governs every step of the fabrication process. The FPC manual must demonstrate how the fabricator controls incoming materials, production equipment, processes, and non-conforming output. Key elements of a robust FPC include:

  • Material Traceability: Procedures to ensure that every structural component can be traced back to its original mill certificate (typically EN 10204 Type 3.1). This requires a reliable system for transferring identification marks from raw material to finished part, often through stamping, tagging, or digital tracking.
  • Equipment Control: A register and calibration schedule for all measuring, testing, and welding equipment. Welders must have calibrated ammeters, voltmeters, and wire-feed speed gauges to ensure they operate within qualified welding parameters.
  • Inspection and Testing: Defined inspection and testing plans (ITP) that specify who inspects what, how, and when. This includes documentation of hold points where fabrication cannot proceed without inspection sign-off.
  • Non-Conformance Management: A formal system for identifying, documenting, evaluating, and correcting products that do not meet specifications.

Welding Quality Management (ISO 3834)

EN 1090 mandates that the manufacturer have a suitable welding quality management system. This is almost universally achieved by complying with the relevant part of ISO 3834.

  • ISO 3834-2 (Comprehensive Quality Requirements) is typically required for EXC3 and EXC4.
  • ISO 3834-3 (Standard Quality Requirements) is typically sufficient for EXC2.
  • ISO 3834-4 (Elementary Quality Requirements) may be acceptable for EXC1.

Welding coordination personnel (welders, engineers, or technicians) must be qualified according to EN ISO 14731. They are responsible for supervising the welding fabrication and ensuring that all Welding Procedure Specification (WPS) are qualified by a Welding Procedure Qualification Record (WPQR) in accordance with EN ISO 15614. Furthermore, all welders and welding operators must be qualified for the specific processes, positions, and materials they are using, per EN ISO 9606.

Material Identification and Traceability

Traceability is a common pain point during audits. The standard requires that materials used in load-bearing structural components are identifiable and traceable from the incoming stock to the erected structure. This involves:

  • Positive Material Identification (PMI): Ensuring the material delivered matches the purchase order and the mill certificate.
  • Marking Transfer: If material is cut, the identification mark must be transferred to the new piece, or a documented system (e.g., a cut-list log) must link the new piece to the original heat number.
  • Inspection Documents: Mill certificates must be retained as part of the technical documentation package. EN 10204 defines the different types of inspection documents (e.g., 2.1, 3.1, 3.2).

Non-Destructive Testing (NDT)

The extent of NDT required is directly tied to the Execution Class. Visual inspection is mandatory for all welds. As the EXC increases, so does the requirement for volumetric and surface defect detection.

  • Visual Inspection (VT): The first line of defense. Inspectors must be qualified to EN ISO 9712.
  • Magnetic Particle Testing (MT) / Dye Penetrant Testing (PT): Used to detect surface cracks and discontinuities in EXC3 and EXC4.
  • Ultrasonic Testing (UT) / Radiographic Testing (RT): Used to detect internal flaws in complete joint penetration (CJP) groove welds. EN 1090-2 specifies minimum percentages of welds to be tested based on the EXC and joint type.

Personnel Competency

Certification extends beyond production control to the competence of the people involved. The manufacturer must demonstrate that all personnel performing activities affecting product quality are competent. This includes welders, NDT operators, welding coordinators, and production supervisors. Records of training, certification, and authorization must be maintained as part of the FPC system.

The Path to Certification

Implementing EN 1090 requires a structured, systematic approach. Most fabricators follow a clear sequence to prepare for and pass the mandatory audit.

Step 1: Scope Definition and Gap Analysis

The first step is to define the scope of certification. What matrix of materials (steel, aluminum) and Execution Classes (EXC2, EXC3) are you targeting? Once the scope is defined, conduct a thorough gap analysis against the current operations. This review will reveal missing documentation, policies, or training requirements.

Step 2: Technical Documentation Submission

The fabricator must compile a comprehensive technical documentation package for the auditing body. This package includes:

  • The FPC manual and associated procedures.
  • A register of WPS/WPQR documents.
  • A register of welder and NDT operator certifications.
  • Material traceability procedures.
  • A register of equipment and calibration records.

Step 3: Selection of a Notified Body

Only an accredited Notified Body (NB) can issue the EN 1090 certificate of conformity. The selection of an NB is a business-critical decision. The NB must be accredited under ISO 17065 and have the correct scope for the material and EXC level. Examples of well-known NBs include TÜV SÜD, SGS, Bureau Veritas, LRQA, and DEKRA. It is wise to review the specific technical expertise of the NB regarding your type of fabrication.

Step 4: The Audit Process (Stage 1 and Stage 2)

The certification audit is conducted in two stages.

  • Stage 1 (Documentation Review): The auditor reviews the technical documentation package to ensure all required procedures are in place and theoretically compliant. This is often performed off-site or in a meeting room at the facility. Non-conformities found here must be resolved before Stage 2.
  • Stage 2 (Implementation Verification): The auditor visits the facility to verify that the procedures are being followed on the shop floor. They will witness welding, check traceability marks, review calibration labels, interview welders, and examine inspection records. The auditor is looking for evidence that the FPC is embedded into daily operations.

Step 5: Certification and Ongoing Surveillance

Upon successful completion of Stage 2, the NB issues the EN 1090 certificate of conformity, which is valid for a period (often three years). However, certification is not a one-time event. The NB will conduct annual surveillance audits to ensure the system continues to function effectively. In the third year, a full recertification audit is required. Non-conformities found during surveillance can lead to suspension or withdrawal of the certificate.

Common Pitfalls and How to Avoid Them

Many fabricators encounter similar challenges during their journey to certification. Awareness of these pitfalls can accelerate the process.

Underestimating Traceability Requirements

Failure to transfer material identification marks from receipt to dispatch is one of the most common findings during audits. Fabricators must implement a robust system, whether it is mechanical stamping, adhesive labels, color coding, or a digital database. The system must be documented and understood by all production staff.

Poor Welding Coordination

Having a welding coordinator on paper is not enough. The coordinator must be competent in the specific welding processes and standards used. Fabricators often struggle to allocate adequate time for this role, which is required to perform functions such as reviewing WPS, conducting weld inspection, and managing welder qualifications.

Incomplete Calibration Records

Every measuring and testing tool used to verify product quality must be traceable to national standards. This includes tape measures, welding gauges, torque wrenches, and ultrasonic thickness gauges. A simple inventory log with unique IDs and calibration due dates is a fundamental FPC requirement.

Benefits & Business Impact

While the primary driver for EN 1090 certification is legal compliance, the operational and commercial benefits are substantial.

  • Market Access: It is the single key to the European structural steel and aluminum market. Without it, a fabricator is confined to non-structural, domestic, or replacement work. It is a prerequisite for involvement in major infrastructure projects.
  • Improved Process Control: The FPC system introduces discipline into the factory. Reduced rework, fewer errors, and better material management directly improve profitability.
  • Competitive Advantage: In tenders, certified fabricators have a distinct edge. General contractors and clients prefer a certified fabricator because it reduces their own risk and liability. Certification serves as an independent verification of quality capabilities.
  • Risk Mitigation: By following a rigorous standard, the fabricator significantly reduces the risk of structural failure, liberating both the business and its clients from significant legal and financial exposure.
  • International Recognition: The EN 1090 system is recognized globally as a symbol of high-quality fabrication, opening doors for international projects often specified to European standards.

Conclusion

EN 1090 certification represents a comprehensive framework for safety, quality, and legal compliance in structural steel and aluminum fabrication. It is not simply an administrative hurdle but a technical and operational system that protects fabricators, clients, and the public. For any company serious about participating in the European construction industry—or in projects requiring a benchmark of structural integrity—achieving and maintaining EN 1090 certification is an indispensable investment. The path requires dedication to documentation, training, and process control, but the result is a more reliable operation and a trusted reputation in the marketplace.