Since July 2014, European companies in the construction industry have been obliged to place load-bearing products made of steel and aluminum on the market within the EU only with a CE mark. The EN 1090-1 standard introduced in 2010 regulates proof of conformity, manufacturer certification and in-house production control.
Execution standard: e.g. EN 1090-2/3/4/5
Design standard: e.g. EN 1990 ff. (Eurocodes)
What is the EN 1090?
In December 2011 the European Union published the new version of the Construction Products Regulation 305/2011 (EU) (previously 89/106/EEC Construction Products Directive). The new regulation now obliges metal processing companies to provide load-bearing components made of steel or aluminium with a declaration of conformity. For this purpose, the series of standards EN 1090 was developed, which consists of three parts:
- EN 1090-1: Execution of steel and aluminium structures – Part 1: Procedures for attestation of conformity for load-bearing components;
- EN 1090-2: Execution of steel and aluminium structures – Part 2: Technical rules for the execution of steel structures
- EN 1090-3: Execution of steel and aluminium structures – Part 3: Technical rules for the execution of aluminium structures
Proof of conformity
The first part of the harmonized European standard (EN 1090-1), deals with the design and manufacture of load-bearing components in the construction industry made of steel or aluminum. The fields of application are load-bearing components, as well as kits, if necessary. If the guide is followed, it can be assumed that components have the specified performance characteristics. This is referred to as a presumption of conformity. A prerequisite for this presumption is (among other things) working according to the applicable parts of the Eurocodes (design standards), as well as the design standards EN 1090-2/3.
Requirements to prove conformity:
- Permissible construction materials can be found in the respective design standards. For steel, this is table 2 of EN 1090-2; for aluminum, table 2 of EN 1090-3 applies.
- The section “Basic tolerances” of the respective design standard describes permissible deviations for dimensions and shape.
- The term “weldable” is also defined. Also materials should be evaluated in thickness direction, if important.
- Materials with suitable fracture toughness must be selected for steel structures. Fracture toughness is not specified for aluminium components. The characteristic values improve with decreasing temperature.
- Declaration of load-bearing capacity, either based on cross-sectional resistance or on the design documents
- Declaration of fatigue strength
- Classification of fire resistance
- Consideration of deformations Limit state of the serviceability
- Fire behaviour according to EN 13501-1
- Release of radioactive radiation or cadmium not permitted
- Requirements Compliance with corrosion protection
Implementation of an Initial Test (ITT)
A first internal test is stipulated in the sense of the Construction Products Regulation. Here, a manufacturer has to show that he is able to manufacture or market load-bearing components in accordance with the standards and the current rules of technology. This initial test must be carried out and documented by the entrepreneur on his own responsibility. If it is determined during or after the test that corrective measures are necessary, the measures must comply with the corrective measures of the design standards.
To carry out the initial test, the manufacturer first groups products into product families. This classification should be carried out as skilfully as possible in order to minimize the effort required for necessary evaluations. It should be ensured that products with essentially the same properties are considered together in a product family. For example, two welded steel structures made of the same base material and the same welding process should be assigned to one family. Components made of materials with lower strength can be assigned to product families with higher requirements. Similar rules exist for the aluminum sector.
Within the examination, the following topics must be checked and documented:
- Tolerance deviations
- Toughness values
- Load capacity
- Fatigue Strength
- Deformation at serviceability limit state
- Fire resistance
- Fire behaviour
- Release of radioactivity and cadmium
- Impact strength
- Permanent Strength
After completion of the initial test, the results must be carefully documented and archived.
Factory Production Control
A further basic requirement, which EN 1090-1 stipulates, is factory production control. The manufacturer is requested to set up, document and check whether products placed on the market have the required performance characteristics. Furthermore, a company has the functioning Production Control certified by a notified body. Often the welding training and testing institutes (SLV) or TÜV offshoots certify the Production Control.
In order to introduce a factory production control in the sense of EN 1090, various documents, controls and tests are usually introduced in the factory and in the operating process. Test plans are also drawn up for components to be manufactured.
Important: If a company has a Production Controlcertified, it must apply it to all products. It is not possible to manufacture products according to EN 1090-1 and others are not.
Where does EN 1090-1 apply?
Initially, EN 1090-1 is mandatory for all companies in the EU that want to produce or market load-bearing components made of steel or aluminum for the construction industry. Here it does not matter whether they only plan or only execute/manufacture. The certificate of the Production Control, as well as the welding certificate according to the execution standards must be available in most cases. And this in every company involved. A “borrowing” of a certificate is often seen, but is not very legally secure.
Companies and enterprises within Europe that want to offer, plan or manufacture steel or aluminum construction and do not have certification according to EN 1090-1 should take care of it as soon as possible. The building product regulation makes it clear. Manufacturing without certification is not legally safe.