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The Keymark is a quality mark from CEN and CENELEC that demonstrates compliance of a product or service with European standards EN

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​The Keymark mark is the sign of conformity with European standards from CEN/CENELEC.

AENOR works with products such as solar thermal collectors and systems, thermal insulators and thermostatic valves for radiators​

The structure of the certification system is the same for both marks: factory visits, sample taking by the inspector and testing (the system is called ISO 5). The basic difference lies in the owner of the Mark. The AENOR N Mark is property of AENOR, and therefore is only granted by AENOR under its own certification systems. The Keymark is property of CEN/CENELEC, and its certificates can be granted by any of its accredited European certification companies. 

When AENOR works in a KEYMARK certification system, it grants both an AENOR certificate and a Keymark certificate to the company.

The Keymark certified products that feature collaboration from AENOR and the respective committees are:

Solar thermal collectors and systems

Thermal insulators

Thermostatic valves for radiators

The certification process is the same as that of the AENOR N Mark. 

First, an application is sent to AENOR. Once it's been studied and accepted, AENOR will conduct the initial visit, sample taking and testing. When AENOR grants the certificate, the monitoring phase begins where annual visits, sample taking and testing will take place. 

Each certification system has specific regulations that detail this process.​

Once the certification process has been completed, the organisation obtains:

  • The Keymark product certification
  • A licence to use the Keymark mark in accordance with the requirements from pertinent regulations
The Keymark product certification

Installation of products

SI Mark for Installation Services

​​​The SI Mark certifies the performance quality of organisations that install products on-site

Thermal insulators

N Mark Certified Product

​​The is recognised as a voluntary mark of quality, which contributes to conforming with the basic requirements of the CTE (Technical Building Code)

Heat convectors and radiators

N Mark Certified Product

AENOR​ ​Mark for radiator and heat convector products

Solar thermal collectors and systems

N Mark Certified Product

AENOR​ ​Mark for solar thermal systems and collectors